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Aarhus University Press |

Urban network evolutions

Towards a high- definition archaeology

Edited by Rubina Raja and Søren M. Sindbæk

Urban network evolutions

Towards a high-definition archaeology

© The authors and Aarhus University Press 2018

Cover by Louise Hilmar

Illustrations: View of the Temple of Artemis in Jerash, Jordan (copyright: Rubina Raja);

Comb cut from multiple pieces of deer antler and assembled with iron rivets. The word ‘comb’ is

carved onto the surface in the Viking runic alphabet (copyright: Museum of Southwest Jutland);

Segmented glass beads found in Ribe (copyright: The Museum of Southwest Jutland);

Glass vessel sherds, beads and other finds from Unguja Ukuu, Zanzibar (copyright: Jason Hawkes).

Back cover: Boats being loaded at Mkokotoni, Zanzibar (copyright: Søren M. Sindbæk).

The book is typeset in Adobe Garamond and printed by Narayana Press

Printed in Denmark

ISBN 978 87 7184 623 2

Aarhus University Press

Finlandsgade 29

DK-8200 Aarhus N

www.unipress.dk

/ In accordance with requirements of the Danish Ministry of Higher Education and Science, the certification

means that a PhD level peer has made a written assessment justifying this book’s scientific quality.

Acknowledgements by the editors 5

Acknowledgements by the editors

The editors would like to thank the Danish National Research Foundation (DNRF

grant 119) for giving us the opportunity to pursue research on urban societies and their

network dynamics in such a grand way, which the grant makes possible. Without the

generous support of the foundation, this book and many other publications, which

have come out over the last few years, would not have been possible to realise. Centre

for Urban Network Evolutions (UrbNet), which is based on the grant awarded by the

DNRF, has grown immensely over the last years and this book showcases much of the

ongoing work undertaken within the framework of the centre.

We furthermore also thank the Carlsberg Foundation for funding several projects,

which have served as springboards for developing the centre idea and which have also

allowed us to run large-scale fieldwork projects testing out some of the ideas developed

within the framework of the centre. A number of other funders should also be thanked

and they have been mentioned in all the relevant contributions.

We are grateful to all funders, who have contributed in a variety of ways to make

UrbNet a reality and let us undertake research, despite the costs, which this involves.

We would also like to thank Mie Egelund Lind and Eva Mortensen warmly for the

minutious copy-editing of the book and for keeping everything together during the

process. Without them the book would not have come together this speedily. Thanks

go to Aarhus University Press for turning around the peer-review process quickly as

well as the lay-out of the book and the printing of it. Finally, the biggest thanks goes

to our wonderful colleagues and staff at UrbNet and in its many projects, who have

contributed their energy and acumen to this great research venture in general and to

the making of this volume in particular.

Rubina Raja and Søren M. Sindbæk, UrbNet, Aarhus

June 2018

Contents

Acknowledgements by the editors 5

INTRODUCTION 11

Urban network evolutions: Exploring dynamics and

flows through evidence from urban contexts 13

Rubina Raja & Søren M. Sindbæk

ROME AND ITS CITIES 19

A high-definition approach to the Forum of Caesar in Rome:

Urban archaeology in a living city 21

Jan Kindberg Jacobsen & Rubina Raja

Burial and birds in pre-urban Rome 27

Nora M. Petersen

Caesar’s Forum: Excavating Italian Iron Age 35

Sine Grove Saxkjær & Gloria Paola Mittica

The Archaic period on the Forum of Caesar:

The urbanisation of early Rome 39

Nikoline Sauer Petersen

A space for Caesar: The heart of Rome and urban development 45

Line Egelund

Caesars, shepherds and cities 51

Trine Arlund Hass

Doliche and the exploration of Graeco-Roman

urbanism in ancient Greater Syria 57

Michael Blömer

Public spaces and urban networks in the Roman Empire:

Messene in the Peloponnese as an example of an approach 65

Christopher Dickenson

PALMYRA: THE URBAN DESERT 73

Urbanizing the desert : Investigating the diversity of urban

networks through the images of deceased Palmyrenes 75

Rubina Raja

Behind the scenes: Cataloguing as a tool for

exploring urban networks 81

Olympia Bobou & Rikke Randeris Thomsen

Producing funerary portraits: An urban tradition in the Syrian Desert 87

Julia Steding

The urbanization of Palmyra: The dynamics of the family cemeteries 93

Signe Krag

JERASH: FROM ROMAN TO ISLAMIC CITY 99

Urban networks and dynamics seen through urban peripheries:

The case of Gerasa on the golden river 101

Achim Lichtenberger & Rubina Raja

Mortar and plaster production in Jerash:

Changing perspective from macro to micro 109

Kristine Damgaard Thomsen

Small change in big cities: Characterising the

development of everyday coinage in Jerash 117

Thomas Birch & Vana Orfanou

River archaeology and urban resilience in Jerash 125

Achim Lichtenberger & Rubina Raja

Urban networks seen through ceramics: Formal modelling

approaches to pottery distribution in Jerash 131

Iza Romanowska, Tom Brughmans, Achim Lichtenberger & Rubina Raja

Medieval Jerash: Investigating the pottery of a Middle

Islamic hamlet in the Northwest Quarter 139

Alex Peterson

Travellers and early urban archaeology in the Levant:

The case of Jerash 147

Eva Mortensen

Archaeoseismology in Jerash: Understanding urban

dynamics through catastrophic events 153

Christian Svejgård Lunde Jørgensen

RIBE: GATEWAY TO THE VIKING AGE 159

Northern Emporium: The archaeology of urban

networks in Viking-Age Ribe 161

Søren M. Sindbæk

3D scanning as documentation and analytical tool:

First field experiences at the Northern Emporium

excavation project, Ribe 167

Sarah Croix

Geoarchaeology and micromorphology at Ribe:

A Northern Emporium in high definition 175

Barbora Wouters

Geoarchaeology of the early northern cities: Microscopic and

geochemical investigations of urban spaces in Denmark 183

Pernille Lærke Krantz Trant

Viking-Age metals and urbanisation: The case of Ribe in Denmark 189

Vana Orfanou & Thomas Birch

A new calibration curve for improved radiocarbon

dating of urban contexts 197

Bente Philippsen & Mikkel Fristrup Schou

Missing links: Viking-Age silver rings and urban networks 203

Mahir Hrnjic

THE MAKING OF MEDIEVAL URBANITY 209

An urban way of life: How to approach the study of networks

and practices in medieval Odense, Denmark 211

Kirstine Haase

Towards the making of a town: Urbanity as practice

and way of life in medieval Copenhagen 217

Hanna Dahlström

The chronology of two medieval cemeteries in central Copenhagen:

Bayesian modelling and archaeo logical relative age information 223

Jesper Olsen, Bjørn Poulsen & Hanna Dahlström

Trade, import and urban development: An archaeobotanical

approach to economic change in medieval Denmark 229

Neeke M. Hammers

Urbanisation and commercialisation on the

periphery of medieval Europe 235

Olav Elias Gundersen

High-definition urban fashion: Proteins reveal preferred

resources for medieval leather shoes 241

Luise Ørsted Brandt

Interdisciplinary methods in town archaeology 249

Johan Sandvang Larsen

Gardening and food security in early southern-Scandinavian urbanism:

Existing evidence and the need for a high-definition approach 255

Søren M. Kristiansen

SWAHILI EMPORIA: AFRICAN NETWORK CITIES 261

Defining space in house contexts: Chemical

mapping at Unguja Ukuu, Zanzibar 263

Federica Sulas & Stephanie Wynne-Jones

Iron production tech nologies and trade

networks in Swahili East Africa 271

Ema Baužytė

Dating Kilwa Kisiwani: A thousand years of East

African history in an urban stratigraphy 277

Stephanie Wynne-Jones, Mark Horton, Jeffrey Fleisher & Jesper Olsen

BETWEEN URBAN WORLDS 287

Through the looking glass: Glass, high-definition archaeology and

urban networks in the 8th century CE from North to South 289

Rubina Raja & Søren M. Sindbæk

About the authors 297

Defining space in house contexts: Chemical mapping at Unguja Ukuu, Zanzibar 263

FEDERICA SULAS & STEPHANIE WYNNE-JONES

Defining space in house contexts: Chemical mapping at Unguja Ukuu, Zanzibar

1. Capturing daily life in urban households

Researching past human activities in houses poses several challenges to archaeological

investigation. The recovery of artefacts and organic remains from house contexts, pottery

and charcoal for example, may be associated with food preparation and/or consumption

and the presence of hearths. However, a number of other routine activities – such as

sleeping and cleaning – and how different spaces were used within the house may not

leave readily visible traces. However, indicators of past activities and spatial organisa-

tion may be preserved at microscopic scale within sediments – the ‘earth’ embedding

archaeological deposits. Soils and sediments represent a valuable archive of information

about the history of a site, whether this be a house, a town or a landscape used in the

past. Yet, the extraction and interpretation of this information remain challenging for

archaeology because soils and sediments are composed of heterogeneous materials and

are subject to mixing and change over time due to natural and human-induced pro-

cesses. In addition, soil markers of past activities are often preserved at a scale beyond

the reach of standard archaeological sciences (French 2015).

Our current research is developing new high-definition approaches to investigate

urban dynamics and transition processes in East Africa. One special focus of research

deals with devising methods to detect, extract and interpret indicators of past conditions

and activities in urban households. In July 2017, the project excavated a sequence of

house deposits at the site of Unguja Ukuu, Zanzibar (Figs. 1 and 2). This essay discusses

some of the key results from chemical mapping of past activities within one house. Here

it has been possible to identify some elements of past activities – particularly in the

enhancement of elements through intensive use of certain spaces – and to distinguish

between roofed and unroofed areas. Our results also show that mainstream archaeo-

chemical approaches to domestic space have limited applicability to the investigation

of past daily life and domestic activities in urban households. High-definition sampling

and analyses of a wider range of elements together with a multi-cluster approach have

enabled us to recover the traces of a former mud house and to identify internal spatial

organisation and possible daily activities.

Federica Sulas & Stephanie Wynne-Jones264

1.1 Archaeological context

Previous exploratory excavations at Unguja Ukuu have recorded the presence of settle-

ment deposits dating back to the 7th century CE, making this site the best candidate

for the origin of coastal urbanism in East Africa. The findings from test trenches feature

both local and imported goods, including materials coming from the western Indian

Ocean (Horton & Clark 1985; Juma 2004; Crowther et al. 2016). A recent site survey

recovered a probable mosque and began a spatial exploration of the site (Fitton &

Wynne-Jones 2017), but until the current research no domestic structures had been

excavated in detail. UrbNet’s first season of excavation exposed the remains of a house

structure with multiple levels of occupation and floors. The house was built of daub, a

material used for thousands of years by several ancient cultures and obtained by mixing

clay, sand, water, plant stuff and, in some cases, animal dung as a binder. Daub houses

are known from archaeological sites along the East African coast spanning the last two

thousand years, and daub is still widely used for house building in fishing villages and

rural areas in the region.

In archaeological contexts, daub houses are very difficult to excavate. Upon abandon-

ment and/or collapse, daub architecture degrades quickly due to soil fauna and mixing.

Such houses may disappear but for a colour staining left on the ground. In our case, the

former presence of a daub structure was just traceable following slight changes in the

colour, texture and compactness of the archaeological sediments. To complicate things

KENYA

SOMALIA

TANZANIA

COMORO

I S L A N D S

INDIAN OCEAN

ZA

MB

IA

MA

DA

GA

SC

AR

MogadishuShell Midden 8

Shell Midden 7

Shell Midden 6

Shell Midden 5

Shell Midden 4

Shell Midden 3

Shell Midden 2

Shell Midden 1

Shell Midden 14

UZ002

UZ001

L. Turkana

L. Victoria

L. Malawi

Lamu Archipelago (Manda, Shanga, Pale, Lamu)

Malindi

Mombasa

Angoche

Irodo

Mahilaka

Sofala

Chibuene

Dembeni

SimaMro Dewa

Kilwa Kisiwani

Songo Mnara

Unguja Ukuu

Pemba Island

MAFIA ISLAND

Zanzibar Island

MO

ZA

BIQ

UE

R. Tana

R. Rufiji

R. Rowuma

R. Zambezi

R. Lim

popo

R. J

ubba

R. S

hebelle

Pottery Scatter (Horton & Clark 1985)

Middens (Horton & Clark 1985)

Coral platform

Mangroves

0 50 100 150 200

Metres

0 500

Kilometres

NN

Map of East Africa and site map (site map produced by T. Fitton, redrawn by L. Hilmar, Grafisk

Tegnestue, Moesgaard Museum).

Fig. 1.


further, the ancient inhabitants of Unguja Ukuu used the same red, sandy materials

to make both the walls and floors of houses. Contextual recording of artefacts and ar-

chaeological features during excavation provided a general layout for spaces and levels

of occupation associated with the house. The findings were particularly rich in local and

imported pottery, metal and glass artefacts and organic materials (shell, animal bone

and plant fragments), covering a period from the late 1st millennium until the mid-2nd

millennium CE. The range and types of findings recovered suggest that the people liv-

ing in this house were engaged in different activities. Archaeological excavation records

were informative but unable to provide conclusive information on key issues such as

the layout of the house, roofed and unroofed spaces and how people lived there. To

answer these questions, the project implemented a high-resolution sampling strategy to

detect potential chemical traces of past activities within floors and occupation surfaces.

2. Methods and materials

The house deposits were investigated using a contextual approach whereby the character-

istics and property of each deposit/context/feature were recorded in detail, all materials

(artefacts, plant/bone/shell remains, etc.) were collected, measured and analysed. Samples

of sediments were taken from floor and surface deposits at 1 m and 0.5 m intervals (Fig. 3).

Laboratory analyses concentrated on establishing two main types of information:

1. Local environmental characteristics and resources, including soils and sediments, and

how these relate to archaeological deposits.

2. Markers of past conditions and human activities preserved in archaeological soils

and sediments.

View of the harbour area of the site, taken during fieldwork in July 2017. The seashore of Menai

Bay is visible in the foreground, characteristic mangrove trees to the left and low grassland vegeta-

tion cover (photo: Zanzibar Urban Transitions Project).

Fig. 2.


The samples collected were then analysed for physical and chemical properties, such as

particle size, organic content and chemical elements. The concentration of 59 chemical

elements was measured using ultra-trace Inductively Coupled Plasma Mass Spectrom-

etry (ICP-MS) on 342 samples. The suite of elements chosen for measurement can be

divided into three main groups:

1. Background, environmental chemical elements that we may expect to find in tropi-

cal, island environments.

2. Elements that can concentrate (or deplete) as a result of human activities (e.g.,

cooking, waste disposal, etc.) and have been found concentrated in archaeological

contexts (Oonk et al. 2009).

3. Elements that are preserved only in trace amounts and have rarely been considered

in archaeological research but may be associated with specific human activities.

3. Results

3.1 Regional soils and archaeological sediments

The first, crucial step was to establish local environmental conditions as a prerequisite

for isolating properties, features and/or components that may be considered ‘intrusive’

and resulting from past human activities.

The site is located along a creek in Menai Bay, western Zanzibar. Here, mangrove

House trench and sampling grid at 0.5 m (photo: Zanzibar Urban Transition Project).Fig. 3.


growth alternates with areas of low grassland that thrive over a (coralline) limestone

geology (Fig. 2). The latter is typical of coastal areas and provides materials for the de-

velopment of red, sandy soils (laterites). In the area, two main soil types were recorded:

a bright red (lateritic), sandy loam and a darkish brown, fine, sandy, silty loam. At the

site, red soils are found under forest and orchard vegetation and are characterised by

relatively high concentrations of organic matter (LOI > 4.5%), and chemical elements

such as iron, copper and zinc – to mention but a few. The dark, brown soil type, instead,

is widely found in tributary valley bottoms and contains much lower amounts of organic

matter (LOI 1.6%) – almost half the amount recorded in the red, sandy soil. In terms of

chemical properties, the dark brown soil type had lower chemical concentrations than

the red soil type but yielded slightly richer amounts of some metallic elements, such as

cobalt, manganese and barium.

Compared with the regional soils, archaeological sediments generally had very low

contents of organic matter and most chemical elements but for enrichment in some salts,

metals and rare earth elements (Fig. 4). The sediments found in the floors yielded higher

contents of organic matter (LOI > 2%) and specific elements including, for example,

aluminium, antimony, barium, potassium, nickel, sodium, vanadium and some rare

earth elements (e.g., cerium, lanthanum). Sediments from other occupation surfaces,

adjoining to the floors and provisionally attributed to external areas, yielded generally

depleted or range concentrations of most elements. In apparent contrast to the floors,

these spaces were enriched in barium, cobalt, potassium, sodium and lead and contained

much depleted concentrations of rare earth elements. Surprisingly, most of the key

chemical elements traditionally considered as anthropic markers in archaeology (e.g.,

calcium, phosphorus, manganese) were virtually absent in our archaeological sediments.

3.2 Indoor spaces

The floors investigated are composed of red sands and contain variable amounts of daub

fragments. The main constituent of such building material is a bright red sand, similar to

the lateritic red, sandy soils and sediments recorded in the area and analysed for chemi-

cal properties. Enhanced levels of elements such as aluminium, caesium and zirconium

in the floors may well reflect the background chemistry of red lateritic sandy material

used for making the daub. However, enrichment of other elements found in the floors,

such as barium, iron, potassium, sodium, strontium, nickel, antimony, vanadium and

rare earth elements (cerium, lanthanum, samarium) cannot be explained in the same

way. Most of these elements can concentrate where organic matter is deposited and/

or used and are relatively stable and resistant once they reach the soil. They have been

found concentrated in archaeological sites, but sources of input may be quite differ-

ent, ranging from wood, bone ash and dung to sea-related resources such as seaweed,

fish and shells. Some metallic elements (e.g., antimony), instead, must be related to

the presence and/or processing of metal-bearing resources, such as lead, iron or even

pigments. Rare earth elements (e.g., cerium, lanthanum, samarium) are quite special

in that they can be released in soils/sediments through what is generally called ‘human

detritus’: that is, residues of skin, hair and nails.


The floor’s chemical signature may thus derive from a combination of things. People

spending time indoors may explain concentrations of rare earth elements, possibly using

(eating?) marine resources, which would release elements such as potassium, sodium

and vanadium. Iron and nickel may be associated with the presence or use of animal

dung (e.g., as fuel or building material).

3.3 Outdoor areas

In contrast with the floors, sandy occupation surfaces yielded a very different chemical

signature: Most elements were found in much depleted contents. Such a pattern sug-

gests that these surfaces were associated with unroofed spaces, kept relatively clean of

Selected chemical element concentrations detected in the house trench (Zanzibar Urban Transitions

Project).

Fig. 4.


waste and possibly less intensively used by people. Enrichment of metallic elements in

these spaces would point to the presence and use of metal-bearing resources and wood

ash (e.g., barium, cobalt, potassium, lead). However, in contexts where metalworking

debris and wood charcoal have been recorded, these elements are found in much lower

concentrations. Another potentially important source of metallic elements are pig-

ments. It is not unreasonable to consider that inhabitants may have used these spaces

for activities involving the use of pigments.

4. Conclusions

The type of chemical enrichment usually linked to anthropogenic impact on archaeologi-

cal deposits appears hardly visible in the house investigated at Unguja Ukuu. This may

be due to local environmental conditions contemporary to the occupation but also to

post-abandonment processes. However, when a wider suite of elements is considered, we

can detect important chemical patterns of spatial organisation. During the excavation,

the division between indoor and outdoor space was sometime impossible to record given

the very nature of house deposits, with standing architecture and floors being made of

the same red, lateritic sandy materials. The determination of the physical and chemical

properties of the sediments spread across the various archaeological contexts enables the

detection of differences between spaces. Rare earth element enrichment seems to mark

the division between different spaces: enhanced levels in the indoor floors; depleted

levels in sandy surfaces outdoors. The floor chemistry appears to reflect the input of

lateritic sands used as building material, the presence of people and possibly the use

of sea-related resources. Outdoor surfaces, instead, may have functioned as patio-like

spaces where specialised activities may have taken place.

In sum, a tight sampling resolution and the analysis of a wide range of elements were

key for detecting different sediment types and associated spaces within the house. High-

resolution chemical mapping was instrumental in establishing chemical concentrations

that may be associated with specific activities. However, elements traditionally used in

archaeological research as anthropogenic markers were not particularly informative in

our house contexts. Had we not expanded the suite of elements to be measured and

developed a cluster-based approach (rather than a single-element one) in the inter-

pretation, we would not have been able to decode the record of uses, conditions and

activities taking place in the house. Clusters of elements, including trace and rare earth

elements, in fact, proved to be particularly sensitive to picking up differences between

roofed/unroofed spaces, intensity of space use and types of activities.

5. Acknowledgements

The research presented here was supported by funds from the Danish National Research

Foundation under the grant DNRF119 – Centre of Excellence for Urban Network Evo-

lutions (UrbNet). We are grateful to Rubina Raja and Søren Sindbæk for their support.

Additional funding was provided by the Swedish Collegium for Advanced Study, Up-


psala; the British Academy; and the School of Culture and Society, Aarhus University.

Excavations and sample export were conducted under permits from the Department of

Antiquities, Zanzibar, and in collaboration with Abdallah K. Ali, Director of Antiquities.

We are especially grateful to the field team and close project collaborators (Abdallah

K. Ali, Ema Baužytė, Wolfgang Alders, Thomas Fitton and Søren M. Kristiansen) and

our assistants and hosts in Unguja Ukuu for making us welcome and for providing

invaluable information and support.

6. Bibliography

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Fitton, F. & Wynne-Jones, S. (2017). Understanding the layout of early coastal settlement at Unguja Ukuu, Zanzibar.

Antiquity, 91 (359), 1268-1284.

French, C. (2015). A handbook of geoarchaeological approaches for investigating landscapes and settlement sites. Oxford:

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Horton, M.C. & Clark, C.M. (1985). The Zanzibar Survey 1984-5. Zanzibar: Ministry of Information Culture and

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Juma, A. (2004). Unguja Ukuu on Zanzibar: An archaeological study of early urbanism. Uppsala: Uppsala University.

Oonk, S., Slomp, C.P. & Huisman D.J. (2009). Geochemistry as an aid in archaeological prospection and site inter-

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Defining space in house contexts: Chemical mapping at