as part of the nomination strategy. Corridors are route segments 
capturing a variety of paths and roads as well as types of unique 
heritage sites along the Silk Roads, 54 main corridors were 
identified from which two along Central Asia and China will be 
nominated in a first phase (Williams 2012). This concept was 
proposed by the ICOMOS Silk Roads Thematic Study based on 
the outcomes of the Ittingen meeting, where the possibility of 
“nominating a series of single properties under a common 
framework (but not constituting a single property)” was 
discussed (Swiss Federal Office of Culture et al. 2010, pp.70— 
71), to find a more sustainable way to carry out nominations 
and manage the sites after their inscription. 
Nominations like the Silk Roads, including more than several 
dozens of sites, require not just good coordination among the 
State Parties involved but also appropriate tools and 
methodologies to properly document the sites. Among the 
Central Asian countries, the Monument Passport System was 
identified as the common inventory system. However, the 
information included is often insufficient for the WH 
nomination or not digitized (Williams 2012). Here, technical 
support is required. One exception is the example of 
Kazakhstan where passport forms are digital and improved 
according to international standards, and the recording 
methodology of heritage sites could be used as a best practice in 
other parts of the region. In response to this need, since 2010, 
the Belgian Federal Science Policy Office (BELSPO) is funding 
together with the support of the WHC, and in collaboration with 
the State Parties involved in the nomination, a three-year 
project: the Silk Roads Cultural Heritage Resource Information 
System (CHRIS). It aims to assist the documentation and 
preparation of the serial transnational Silk Roads WH 
nominations as well as their later management and monitoring 
with the development and implementation of a Geospatial 
Content Management System (GeoCMS). 
2. DOCUMENTATION WITH GEOSPATIAL 
CONTENT MANAGEMENT SYSTEM 
Documentation is the first step to understand the heritage sites 
and their context. This is achieved by gathering adequate 
baseline information on values, stakeholders, physical condition 
and management practices (Demas 2002), data that could be 
recorded, structured and shared in an easier manner with the use 
of IMS. 
The physical conditions of the site or monument as well as the 
threats and causes of deterioration could be recorded by 
different surveying techniques from direct hand measurements 
to advanced digital technology such as laser scanners or remote 
sensing tools, depending on the complexity and scale of the site 
(Bryan et al. 2009). This variety of tools produces different 
types of data that later are integrated in a single system. In case 
of serial transnational nominations, this task is more complex as 
a large volume of data has to be handled. Metadata and data 
standardization are also essential, as information needs to be 
shared among several stakeholders. The geographical location 
of the sites plays a crucial role to better understand the context, 
gather additional information about the sites or perform 
comparative or advanced analysis on them such as identifying 
the trend of threats affecting the properties. To support the latter 
task, Geographic Information Systems (GIS) and Remote 
Sensing proved to be valuable tools (Hernandez 2002). 
2.1 GIS and Remote Sensing as tools for documentation 
and detecting changes 
GIS and Remote Sensing are tools increasingly often used in 
conservation of cultural and natural heritage. GIS has emerged 
as a mean to manage and analyse information more efficiently 
and effectively (DiBiase et al. 2006). This tool not only answers 
questions such as "what" or "when" but specifically the "where" 
question by creating relationships between the data and the 
spatial information recorded in a database (Longley et al. 2011). 
GIS includes spatially, non-spatially and temporally related 
features. In the example of cultural heritage, spatial features 
provide always a location showing e.g. how close the sites are 
related to other objects or which sites are within certain 
boundaries; non-spatially related information show for example 
the gender of the person buried and temporally related to e.g. 
time dates. These attributes brought together in a GIS 
environment have the capability to keep track of all the data 
acquired, classify it in different types, and allow its spatial 
visualization and analysis. 
GIS has a variety of applications in cultural heritage. It is 
mainly used in field work to record data of excavations, in 
modelling to create surface models to locate archaeological 
remains, in resource and data management or land use 
archaeology to prepare data for future field survey. 
Some common GIS applications for cultural heritage are spatial 
queries, thematic maps, or management of remote sensing data. 
First, spatial queries display the spatial information rapidly 
enough to find additional information on e.g. topological 
connections or relationship between objects, distribution of 
survey data to visualize site development in the past or in 
tourism management, by performing complex analyses that 
allow for customized maps, charts and statistics, e.g. 
superimposing layers. Second, thematic maps developed out of 
the data illustrate e.g. the distribution of objects or sites within 
an area (Longley et al. 2011). Finally, remote sensing 
technologies include the use of (1) satellite images, (2) 
prospection and (3) digitization. 
(1) Satellite images are commonly used to identify new sites 
and delimit boundaries (composite satellite images) or changes 
(multi-temporal images) as shown in the examples below. 
Aminzadeh and Samani (2006) implemented the use of 
composite satellite images to delineate the ancient boundaries 
of Persepolis in Iran. A combination of Landsat ETM+, black 
and white aerial images and topographic maps, was used to 
detect archaeological features and remains of possible guard 
walls and watchtowers. Barlindhaug et al. (2007) applied the 
multi-temporal images method to detect natural re-growth 
processes and to identify archaeological sites threatened by 
these processes. This study used the bands of Landsat images of 
three archaeological sites in Norway to calculate the 
Normalized Difference Vegetation Index (NDVI) used to 
differentiate vegetation from other types of land use. For 
visualization purposes, including temporal changes, Google 
Maps satellite view offered as background layer could be an 
affordable solution. For example, it is possible to view images 
from several acquisition dates by using the timeline application, 
with which temporal changes can be visualized, such as the 
shrinkage of the Aral Sea. (2) Prospection is a non-destructive 
method useful e.g. in archaeology to discover new sites or to 
identify the full extent of the site and define and map the 
relevant areas, without actually disturbing the site. Common 
remote sensing prospection techniques are aircraft-mounted 
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