Viewshed Analysis and Intersite Visibility of Iron Age Castros in Northern Portugal. Jordan Bowers GEO 386G

Transcrição

1 Viewshed Analysis and Intersite Visibility of Iron Age Castros in Northern Portugal Jordan Bowers GEO 386G Fall 2014

2 Table of Contents Introduction...1 Data Acquisition and Modification...2 Digital Elevation Model...2 Creation of the Geodatabase...2 Study Area Vector Layer...2 Political Geography of Northern Portugal...3 Hydrogeography of Northern Portugal...3 Name and location of Castros...4 Viewshed Analysis...4 Intersite Visibility Analysis...5 Conclusions...6 Map 1: Castros and Municipalities of Northern Portugal...8 Map 2: Viewshed from Cividade de Bagunte...9 Map 3: Viewshed and Visible Sites from Cividade de Bagunte...10 Map 4: High Certainty Intersite Visibility Network of Northern Portugal...11 Map 5: Intersite Visibility Network in Northeastern Portugal...12 Table 1: Castros of Northern Portugal by Number of Sites Visible...13 Works Cited...16 i

3 Introduction The Castro Culture is a culture group from Northern Portugal and Galicia that inhabited the region from circa 1000 BCE, at the beginning of the Iron Age, until assimilation into the Roman Empire in the first century CE. The archaeological record is dominated by fortified, hilltop settlements known as castros. Castros are differentiated in size with three different designations: Castro, Cividade, and Citania. Cividade and Citania are reserved for the largest castros, which may cover 25 hectares or more, although these designations are largely up to the interpretation of the excavators. The core area of the Castro Culture was along the Ave River and its tributaries in Northern Portugal, but castros have been excavated from the Douro River to the northern coastline of Galicia. My research in the region is currently over the connection between visibility and power. I look at the role visibility plays at two levels: at the local level, particularly with regards to Cividade de Bagunte, and at the regional level covering the entire area of the Castro Culture. Broader questions I seek to answer are how did a site s location permit and secure control over the site s surrounding landscape and how did a dominant site s geographic position relate to other smaller castros within its viewshed? My dissertation research draws upon the theoretical approaches of both landscape archaeology and settlement archaeology to create a more accurate understanding of the relationships between humans, sites, and landscapes. To study the patterns of settlement and use of landscape as an entangled system unlocks the realities of past boundaries from modern Western perceptions (Bruck and Goodman, To consider the concept of boundaries from modern and prehistoric viewpoints it is imperative to study the taskscape, the nonstatic physical and social changes that occur in a landscape over time through human labor, which plays a role in the development of the landscape and one s interpretations of it (Ingold, My research focuses on sites as taskscapes and how the inhabitants of each site utilized the landscape. I am attempting to understand the ways in which expressions of power and control affect the way the inhabitants of the site mentally viewed, constructed, and navigated their physical space. I am applying GIS software as a heuristic tool to understand the processes and conceptions of the landscape as perceived by an individual (cf. Llobera, Viewshed analysis and intersite visibility analysis were necessary for this project in order to begin answering questions about how visibility plays a role in the expression of power and dominance. In their study of Inca sites, Kosiba and Bauer have shown that political and social configurations can be expressed by the location of sites within the physical landscape, particularly by controlling aspects of visibility (2013. It has been noted that the existence of a visibility network among sites may play a role in how a site and its inhabitants recreate their environment in response to limitations caused by natural features, such as ridges (Christopherson and Guertin, The visibility network between castros in Portugal has previously been studied (Dinis, 1993, however his study was limited to a dataset if only 25 castros along the Lower Ave River Valley. My study expands on the Dinis s work and includes another 92 castros. I expect to find in this study that Cividades and Citanias have the largest viewsheds and largest number of sites visible. 1

4 Data Acquisition and Modification The data required for this project included: Digital Elevation Model for Northern Portugal Shapefile for the delineation of the study area Political geography of Northern Portugal, including an outline of the districts and country and name and locations of municipalities Hydrogreography of Northern Portugal Names and locations of castros Digital Elevation Model The DEM used for the project came from publicly available ASTER data. I set the projection to WGS 1984 UTM Zone 29N, as this is the same coordinate system and projection we use for our field research in the region. I used the ProjectRaster tool from the toolbox to apply the projection to the DEM. This allowed to me to create a hillshade and to take into account the curvature of the earth in the viewshed analysis. Figure 1 shows the DEM with a stretched color ramp, dark green showing the lowest elevations and brown the highest. The DEM included data for elevations at 0 meters or lower, which was necessary for creating a vector polygon for the Atlantic Ocean later on. Figure 1: DEM from ASTER data Creation of the Geodatabase Following the importation of the DEM, it was necessary to create a geodatabase to keep all the data organized. I created three feature datasets, one each for political geography, hydrogeography, and the castros. I also created a feature class that would be used to delineate the study area. Study Area Vector Layer After adding the DEM to ArcGIS, I created a polygon within the study area feature class that included all of Portugal north of the Douro River, some areas of Spain, and the Atlantic Ocean. I then used this layer as a mask to clip the DEM to the study area. This polygon was also used as a mask to clip all of the other data imported in order to ensure that shapefiles would not extend outside of the study area. 2

5 Political Geography of Northern Portugal For the Political Geography feature class, I imported the administrative regions and country outline downloaded from DIVA-GIS. I found a shapefile for all municipalities in Portugal from MapCruzin.com. I edited this shapefile in order to only show the largest towns within the districts in Northern Portugal and corrected many errors caused by special characters in the names. Figure 2 shows the modified shapefiles for the political geography of northern Portugal, The thick, gray outline represents the outline of Portugal, the thinner lines are the borders for the districts, and the points are for the municipalities. Figure 2: Modified shapefiles of the political geography of Northern Portugal Hydrogeography of Northern Portugal From the DEM, I created a raster of the Atlantic from all elevations which were less than or equal to zero, which was then converted into a vector layer. I then edited the Atlantic Ocean vector to clean up some of the irregularities that remained from the DEM, then used the Dissolve tool to further clean up the layer. I then imported shapefiles for the rivers and lakes in Portugal that I downloaded from DIVA-GIS. These shapefiles were overly simplified and when zoomed in did not match up with the valleys in the DEM. I used LandSat imagery to edit these shapefiles to create more accurate lines for the rivers and polygons for the lakes. Figure 3: Shapefile showing the Atlantic Ocean and the modified rivers and lakes 3

6 Name and Locations of Castros To find the longitude and latitude for the castros in Portugal and Galicia, I used two main sources, Ordenamento do Territorio do Baixo Ave no I Millenio A.C. by Antonio Pereira Dinis and Megalithic.co.uk. Dinis gives the names and locations for 25 castros along the Lower Ave River Valley, although he does not state which datum he is using for his coordinates. However, when projected using the WGS84 datum, these sites appear to fall in the correct location, so it is probable that this is the datum he used. To get data for other castros within Portugal, Megalthic.co.uk contained names and coordinates for many other sites, however I am unsure of the accuracy of the coordinates given for each site. A spreadsheet (see Table 1, p. X containing the listing of sites and their coordinates was imported using the Import XY Data function and were then added to the feature dataset castros. The collection of these data allowed me to create a map of castros in Northern Portugal in relation to the political and physical geography of the region (see Map 1, p. 8. Viewshed Analysis The viewshed analysis tool in ArcToolbox was applied to each site within the study area. This tool identifies all cells visible from a particular point on a projected DEM raster and can even take into account refractivity and earth curvature, which was necessary because the study area was so large. The viewshed analysis results in a binary raster where 0=not visible and 1=visible. The tool was unable to run for all castros within the study area and return individual results for each site. This made it necessary to create individual point feature classes for every site, after which each site had to be run through viewshed analysis. Figure 4 shows an example of how I used the Viewshed tool for each site. On the attribute table for each site point I added the column OFFSETA and entered a value of five meters. This meant that when the viewshed tool was running it would calculate the observer point as being five Figure 4: Example of viewshed tool as applied to each site meters higher than the elevation of the cell. I decided to use an offset value in order to see the viewshed as it would be seen from the top of a wall or watchtower, as opposed to within the actual site where one likely would have not been able to see outside the site. The result was an individual binary raster for each site showing which cells on the DEM were visible or not from the theoretical watchtower. 4

7 For each raster, I changed the symbology to only display the cells that are visible and set them to 60% transparency so that overlap of viewsheds would be visible. The overlap is currently not important for my research, but may be beneficial in answering later questions that may come up regarding areas of shared visibility. I then gave each raster a unique color in order to differentiate the visibility for each site. There is some possible overlap in colors, as applying 117 distinct colors is a bit difficult, but showing and hiding the various layers can assist in differentiating viewsheds with similar colors. Figure 5 shows a combination of all viewshed rasters, which gives an overall idea Figure 5: Viewshed for all castros in Northern Portugal of the total extent of visible areas from all sites. Map 2 (p. 9 shows the viewshed for only Cividade de Bagunte, including other visible sites. A future goal from this research is to calculate the total area visible from each site, however the DEM will need to be refined before an accurate number can be achieved Intersite Visibility Analysis From the results of the viewshed analysis, I created a new line feature class for intersite visibility. This layer shows lines between sites that mark the visibility between castros. I categorized the lines into two types based on the certainty of the visibility. The certainty for each line came from the location of sites in conjunction with the viewshed. When testing for visibility, if a site fell within the areas marked as visible in the viewshed raster I marked it as having high certainty. If the site was separated from visible areas, but only by a few cells, I assigned the low certainty attribute to the line. Map 3 (p. 10 shows the results of the visibility analysis for only Bagunte in combination with the viewshed raster. The results of this analysis for a single site mirrors the results of the viewshed analysis, but only as the viewshed relates to other sites. Combining the lines for intersite visibility for all sites within the study area a clear network of visibility forms (see Map 4, p. 11. The sites in Northwestern Portugal form one grouping with a high level of connectivity, as shown in Map5 (p. 12. This grouping is distinct from the sites in Northeastern Portugal, which show some connectivity, but many of the sites are not visible from each other. It is possible from this analysis to question the validity of classifying the sites in the eastern portion of the study area as being part of the Castro Culture, however it is also necessary to include material culture if a distinction is to be made. 5

8 Conclusion It is necessary to expand upon this project in the future. There are a number of issues related to the data, particularly from the DEM and castros, that could cause results of the analyses to change. It appears that the DEM includes buildings and foliage in its measurements of elevation. This means that a stand of trees may block a large section of the viewshed now, whereas this may not have been the case during the Iron Age. Additionally, many of these sites are surrounded by tall eucalyptus trees, which would also limit the viewshed from the acropolis of each site. This was the case at Bagunte, where I had to find the highest elevation and move the observer point there in order to get a better result from the viewshed analysis. The issues stemming from the ASTER DEM can be rectified through using other sources of information for elevation, such as topographic maps or LIDAR data. I will also be performing research during upcoming field seasons on pollen and phytoliths dating to the Iron Age. The results of this research should give a better idea of what species of plants, particularly trees, were growing in the region and at what density. The difference between thick forests and open plains can vastly change a viewshed, and thus the visibility network between sites, so it will be necessary to take this into account. The list of castros and their coordinates may also have caused some errors in the data. Many of these coordinates were collected from the internet and the accuracy of them is unknown. Many of the coordinates were not accurate enough to place a point exactly where the site would be. Rectification of this would require that each site be visited and its coordinates remeasured. It is also possible that the list is incomplete. Dinis s listing only gives coordinates for castros in the valleys of the Ave and Este Rivers. Additionally, the Megalithic Portal does not appear to have a complete listing of castros for Portugal and it is possible that many outside of the area discussed by Dinis were not included in this analysis. Map 1 highlights this discrepancy, as a clear concentration of sites is evident along the Ave River and only a few appear north toward Spain. The results of these GIS analyses offer insight into the role that visibility played within the Castro Culture. There must have been a reason for these societies to settle along hilltops. There is little to no evidence for war or battles between the castros, but the geographic position of the settlements in combination with large walls points at the need for the culture to settle in easily defendable areas. The intersite visibility analysis highlights the connection between almost all of the settlements commonly identified with the Castro Culture in Portugal. The vast network would allow information to be exchanged quickly between settlements. Table 1 lists the castros included in the study area. Columns are included with the number of sites visible from each location, which is then broken down to the number of sites where the certainty of visibility is high and low. The results of this backed up my expected results that Cividades and Citanias would have the greatest number of sites visible. However, there were a few unexpected results. Monte da Falperra was much higher than expected, with 31 total sites visible and also had the greatest number visible with high certainty (22. Equally surprising was the position of Citania de Briteiros. Briteiros is one of the largest and best well documented castros in Portugal, however the number of sites visible from it was much lower than expected. Following with the idea that Citanias and Cividades would have the highest number of sites visible, it is surprising the Citania da Longa had absolutely zero visibility. However, the location 6

9 of this castro may lend itself to part of a network of Galician castros. It is also possible that Longa was designated as a Citania due to sociopolitical factors when these sites were first excavated. A continuation of this project will be necessary to get at the larger questions regarding visibility, power, and control, but refinement of the data used to draw these inferences must occur in order to improve the accuracy of the results. 7

10 Map 1: Castros and Municipalities of Northern Portugal Pontellas Baiona Xián Spain ho Mi 42 0'0N 8 0'0W Troña 7 30'0W San Amaro São Caetano io R Vila Nova de Cerveira Santa Tecla Pintán Coto da Pena Ancora Coroa Vieito R im io L Xironda Sacóias a Gimonde Bragança Montalegre a io Limda Barca RPonte Chaves São Romão Terras de Bouro Alto das Valadas Viana Tras do de Castelo Cidades Cresto São Julião Sabariz Roques Vila Verde Barbudo Redondo Amares Carmona Cavalhelhos Lama de Ouriço Cabeço Santiago do Monte Vilarendelo Vilanova Loivos Valpaços Boticas Lesenho Vieira do Minho Giestosa Castelo do Neiva Belinho Povoa de Lanhoso Monte Castro Eiras Velhas Monte do Castelo Máximo Monte dos Picos Nossa Senhora da Paz São Lourenço Barcelos Nandunfe Pau de Bandeira Esposende Pedrais Braga Cabeceiras de BastoRibeira de Pena Briteiros Sr. dos Desamparados Ferreiros Picotos Sabroso Lages S. Bartolomeu Ermidas Forca Fafe Cerva Guimarães Saia Bóca Santo Ovidio Alto das Eiras Mondim de Basto Penices Terroso Cruito Crastoeiro Santa Tecla Casais Celorico de Basto Facho Povoa de Varzim S. Miguel-o-AnjoVizela Felgueiras Bagunte 41 30'0N São Juzenda Macedo de Cavaleiros Murça Palheiros Amarante Vila Flor Sabrosa Alijo Maia Paredes Penafiel Marco de Canaveses Valongo Serra do Muro de Vadoma Cidadelhe Mesão Frio Porto Gondomar Vila Nova de Gaia Monte Mozinho Tabuaço o Armamar our Resende Lamego io D Guedes R Arados Cinfães Rio Melgaço o Longa D o ur Castelo de Paiva Tarouca Viseu Espinho Moimenta da Beira Fiães Aveiro Ovil Cabeço dos Mouros Romariz Monte Castelo Matosinhos Vicente Mogadouro Alfandega da Fe Populo Carrazeda de Ansiaes 41 0'0N WGS84 UTM Zone 29N 1:750, '0W ¹ '0W '0W 50 Kilometers Baldoeiro Alfarela Torre De Moncorvo Moncorvo Torroso São João da Pesqueira Atlantic Ocean 9 0'0W Aldeia Nova Bragança Vila doretorta Conde Vila Real Vale de Aguia Mirandela Braga Trofa Torre Alta Santa Margarida S. João Santa Marinha Monte Padrão Sanfins Boi Alvarelhos Paços de FerreiraLousada S. Paio Cirigata São Brás Ribas Vila Real Porto Pedrario Cendufe Ponte de Lima Paredes de Coura Cossourado Viana do Castelo Formigoso Cidade Spain Alvora Coto de Ouro Azere Arcos de Valdevez São Martinho 7 0'0W Melgaço Altamira Valença n Gondomar 42 0'0N 8 30'0W '0N 9 0'0W Freixo de Espada a Cinta Freixo de Numao Penedono Guarda Spain Meda Lumbrales 7 0'0W 41 0'0N Castros Rivers Country Border Municipalities Lakes District Border

11 9 Map 2: Viewshed From Cividade de Bagunte 8 30'0W 8 0'0W Coto de Ouro São Martinho Coto da Pena Azere im Rio L Cendufe a Pedrario Formigoso Viana do Castelo Vieito Tras de Cidades São Romão Alto das Valadas Cresto Roques Sabariz Carmona Castelo do Neiva Monte Castro Nossa Senhora da Paz Ri av oc do Vasoncelos Lesenho São Lourenço 41 30'0N Picotos Braga Eiras Velhas Monte dos Picos Pedrais Lages Retorta Bagunte Santogões S. João Santa Marinha e Rio Av Ri o V Vila Real Sabroso Cerva Santo Ovidio Crastoeiro izela Torre Alta Santa Margarida Sanfins Monte Padrão Boi Alvarelhos S. Paio Nandunfe Falperra S. Bartolomeu Forca Ermidas S. Miguel-o-Anjo Saia Bóca Cruito Alto das Eiras S. Miguel-O-Anjo Vermoim Santa Cristina Santa Tecla Penices Terroso Facho S. Miguel-o-Anjo Casais Monte do Castelo Briteiros Bagunte Argifonso Loivos Giestosa Máximo Santa Maria de Galegos Consolação Ferreiros Sr. dos Desamparados Cabeço Barbudo Redondo a Belinho Cavalhelhos São Julião 41 30'0N Ancora Coroa 7 30'0W Porto Torroso Serra do Muro de Vadoma Monte Mozinho o r ou R io D Guedes WGS84 UTM Zone 29N 1:375,000 ¹ ur o 8 30'0W Bagunte 0 Castros Rivers 8 0'0W 5 Lakes Do R 10 io Monte Castelo Cidadelhe 20 Viseu 30 District Border Km 7 30'0W Visible Areas

12 WGS84 UTM Zone 29N 1:325, Map 3: Viewshed and Visible Sites from Cividade de Bagunte 8 30'0W Vila Real Alto das Valadas Tras de Cidades Cresto Viana do Castelo 8 0'0W São Julião Roques Sabariz Barbudo Redondo Carmona Castelo do Neiva Belinho Braga Sr. dos Desamparados Ri o C Alto da Cividade ado av Máximo Ferreiros 41 30'0N Picotos Saia R io Terroso ste E Penices Casais Bagunte Argifonso Bagunte S. João Santogões Santa Marinha Ermidas Castros Rivers Ri oa Santo Ovidio Alto das Eiras Vermoim Santa Cristina Facho Santa Tecla S. Miguel-o-Anjo Rio Viz ela Torre Alta Santa Margarida Sanfins Monte Padrão S. Paio Bagunte Sabroso S. Miguel-o-Anjo Bóca S. Miguel-O-Anjo Cruito Alvarelhos Monte Castelo Falperra Briteiros S. Bartolomeu Forca Boi ¹ Nandunfe Consolação Pedrais Lages Retorta 41 30'0N Santa Maria de Galegos São Lourenço Vasoncelos Monte dos Picos ve Nossa Senhora da Paz Monte do Castelo Eiras Velhas Monte Castro Porto Torroso Lakes Serra do Muro de Vadoma 8 30'0W District Border Visible Areas High Certainty 20 Km 8 0'0W Low Certainity

13 41 50'0N 41 40'0N 41 30'0N 41 20'0N Pintán Santa Tecla 8 50'0W R io Minho 8 40'0W 8 30'0W 8 20'0W 8 10'0W 8 0'0W 7 50'0W 7 40'0W 7 30'0W 7 20'0W Cossourado Alvora São Martinho Coto de Ouro Azere Coto da Pena Viana do Castelo Cendufe Pedrario Ancora Formigoso São Romão Coroa Vieito Lama de Ouriço Alto das Valadas Cavalhelhos Tras de Cidades Cresto Cabeço Sabariz São Julião Santiago do Monte Roques Vilarendelo Barbudo Lesenho Carmona Redondo Vilanova Giestosa Loivos Castelo do Neiva Belinho Monte Castro Ribas Eiras Velhas Monte do Castelo Máximo São Lourenço Nandunfe Vila Real Ferreiros Alto do Crasto Pedrais Briteiros Braga Picotos Sabroso Lages S. Bartolomeu Forca Saia Bóca Santo Ovidio Cerva Alto das Eiras Terroso Penices Cruito Palheiros Santa Tecla Crastoeiro Casais Facho S. Miguel-o-Anjo Bagunte Retorta Populo Santogões Torre Alta S. João Santa Marinha Santa Margarida Boi Sanfins Bragança Alvarelhos Monte Padrão S. Paio Rio Lima Map 4: High Certainty Intersite Visibility Network of Northern Portugal Rio Lima '0N 41 40'0N 41 30'0N 41 20'0N Porto 41 10'0N Monte Castelo Torroso Serra do Muro de Vadoma ¹ Monte Mozinho Guedes Arados 8 50'0W 8 40'0W 8 30'0W 8 20'0W 8 10'0W Rio Douro WGS84 UTM Zone 29N Scale: 1:550,000 District Border 8 0'0W Rio Douro Cidadelhe Viseu Guarda Km 7 50'0W 7 40'0W 7 30'0W 7 20'0W Lakes Rivers Castros High Certainty of Visibility 41 10'0N

14 8 50'0W Map 5: Intersite Visibility Network of Northeastern Portugal 8 40'0W 8 30'0W 8 20'0W 8 10'0W '0N Roques Sabariz Carmona Barbudo Redondo 41 40'0N Castelo do Neiva Belinho Nossa Senhora da Paz Rio C avado São Lourenço Sr. dos Desamparados Picotos Monte Castro Santa Maria de Galegos Alto da Cividade Máximo Ferreiros Eiras Velhas Vasoncelos Monte dos Picos Alto do Crasto Consolação Falperra Briteiros Pedrais Sabroso Monte do Castelo 41 30'0N Lages R io Ave 41 30'0N Terroso Casais Argifonso Bagunte Saia Penices Rio Este S. Bartolomeu Forca Ermidas S. Miguel-o-Anjo Bóca S. Miguel-O-Anjo Cruito Alto das Eiras Vermoim Santa Cristina Santa Tecla Facho S. Miguel-o-Anjo Rio Vizela Santo Ovidio Retorta S. João Santogões Santa Marinha Torre Alta Santa Margarida 41 20'0N A t l a n t i c O c e a n Boi Sanfins Monte Padrão 41 20'0N ¹ S. Paio Alvarelhos Km 8 50'0W WGS84 UTM Zone 29N Scale: 1:250, '0W District Border Lakes 8 30'0W Rivers Castros 8 20'0W High Certainty of Visibility 8 10'0W Low Certainty of Visibility

15 Table 1: Castros of Northern Portugal by Number of Sites Visible Site Latitude (DD Longitude (DD Number of Sites Visible High Certainty Low Certainty Monte da Falperra Cividade de Bagunte Monte da Saia Citania de Sanfins Castro do Facho Castro do Alto das Valadas Castro de S. Miguel-o-Anjo (Ruivães Castro de Carmona Castro de São Lourenço Castro de Barbudo Castro de Alvarelhos Monte dos Picos Castro de Consolação Castro do Monte Padrão Monte de S. Bartolomeu Cividade de Terroso Castro de Santa Tecla Castro de Lages Alto da Cividade Alto do Crasto Citania de Sabroso Citania de Briteiros Castro Máximo Castro da Serra do Muro de Vadoma Citania de São Julião Eiras Velhas Castro de S. Miguel-o-Anjo (Vermil Pedrais Monte de Vasoncelos Monte da Forca Monte do Castelo Castro do Sr. dos Desamparados Castro de S. João Castro de Monte Castro Castro de Santa Cristina Pau de Bandeira Santa Maria de Galegos

16 Castro da Bóca Castro do Boi Castro de Santa Margarida Monte Redondo Castro das Ermidas Alto das Eiras Castro de Vermoim Castro de Monte Mozinho Castro de Sabariz Castro de Vilanova Cividade De Belinho Outeiro dos Picotos Castro do Vieito Castro de Casais Castro do Cruito Castro de Tras de Cidades Castro do Cresto Monte do Castelo do Neiva Castro de Santiago do Monte Castro de Nandunfe Castro da Retorta Castro do Formigoso Torre Alta Castro de Argifonso Castro de S. Miguel-o-Anjo (Calendário Castro de São Juzenda Castro de Roques Castro de Lesenho Castro de Fiães Castro de Nossa Senhora da Paz Castro de São Brás Castro da Corôa Castro de Ribas Castro de Ferreiros Castro de S. Paio Castro do Coto de Ouro Castro de Vilarendelo Castro do Guedes Castro de Cendufe Cividade de Ancora Castro de Melgaço

17 Castro de Carvalhelhos Castro de Santagões Castro Romariz Castro de Sacóias Castro de Cirigata Castro de São Martinho Cividade do Cossourado Castro do Populo Castro do Pedrario Castro de Palheiros Castro da Lama de Ouriço Castro do Cabeço dos Mouros Muralha das Portas de Montemuro Castro de Santa Marinha de Ferreiró Castro de Penices Castro de Ovil Castro do Monte Valinhas Castro de Santo Ovídio Castro de Gimonde Castro de Aldeia Nova Castro de Vale de Aguia Castro Vicente Castro de Baldoeiro Cabeço de Alfarela Castelo Velho de Freixo de Numao Castro dos Arados Castro do Monte Castelo Castro de Azere Povoado Castrejo de Alvora Coastro do Coto da Pena Castro de São Caetano Castro de Cabeço (Granja Castro da Giestosa Castro de Loivos Castro de Cidadelhe Castro de Crastoeiro Castro de São Romão Castro da Cerva Citânia da Longa

18 Works Cited Bruck, J. and M. Goodman. (2003 Introduction: themes for a critical archaeology of prehistoric settlement. In Making Places in the Prehistoric World: Themes in Settlement Archaeology. Eds. J. Bruck and M.Goodman Routledge. Christopherson, G and D. Guertin (1996. Visibility Analysis and Ancient Settlement Strategies in the Region of Tall al-umayri, Jordan. University of Arizona. Web. 2 Dec Dinis, A (1993 Ordenamento do Territorio do Baixo Ave no 1 Milenio A.C. (Unpublished doctoral dissertation. Faculdade de Letras da Universidade do Porto, Portugal. Ingold, T. (1993 The Temporality of the Landscape. World Archaeology 25: Kosiba, S. and A. Bauer (2013 Mapping the Political Landscape: Toward a GIS Analysis of Environmental and Social Differences. Journal of Archaeological Method and Theory 20: Llobera, D. (1996 Exploring the topography of mind: GIS, social space and archaeology. Antiquity 70: