Key features of geospatial data are:

Location-based: includes coordinates (X/Y), addresses, or other georeferenced information. 

Geometry: It represents the real-world features in different formats, such as points (e.g. listed buildings), lines (e.g. roads), and polygons (e.g. conservation area) 

Attributes: Each feature has associated descriptive information (e.g. historic building’s name, construction date, or conservation status) 

Spatial Relationships: It defines how objects relate to each other in space (e.g. proximity, adjacency, containment) 

Projections and Coordinate Systems

Map Projections is a way to flatten our 3D world into a 2D view. Frequently used are: 

1. British National Grid (BNG) – EPSG:27700 

• Type: Transverse Mercator 

• Used for: Ordnance Survey (OS) mapping and official UK geospatial datasets 

• Limitations: Not valid outside Great Britain (excludes Northern Ireland) and now useful for global datasets 

 2. WGS 84 (World Geodetic System 1984) – EPSG:4326 

• Type: Geographic coordinate System (lat/long) 

• Used for: GPS, global and web mapping allocations 

• Limitations: Distances and areas are distorted 

 3. Irish Transverse Mercator (ITM) – EPSG:2157 – also covers NI 

4. For working with European datasets: ETRS89-based projections 

What analysis can you do with the data?

• Interrogation of data (querying by location or attribute – pattern distribution, relationships and proximities) 

• Viewshed analysis (visibility modelling) 

• Cost-surface analysis (modelling movement across landscapes) 

• Predictive modelling (climate change etc.) 

• Time Series Analysis (track changes, detect patterns, and make predictions) 

4. How does GBPT use GIS?

And how can you use GIS …

• Doors Open Day Visitor Analysis – use survey data to map attendees postcode data, gender, age, disability and places visited. Great tool to map what areas are most likely to get involved and who they need to reach out more to. Also great to find data for funding applications. 

• Historic GBPT Projects – integral part of management of 40+ year archive. Distribution of capital projects and consultancy work. Types of buildings, dates etc. 

• Current GBPT projects – identifying barriers and visualising data for funders 

• Developing mobile GIS – citizen mapping projects 

Positives/benefits of GIS

• Easily manage and maintain large volumes of digital data 

• Ability to output in many different formats and cater to different audiences/clients 

• Excellent interpretative and visual aid to research 

The not so good 

• Output can only ever be as good as captured data – ‘garbage in, garbage out’

• Medium becomes the message – technology can eclipse content, critical ‘rigour’ is undermined 

• Accuracy and precision issues, particularly with disparate datasets 

• Need to be checked and updated  

• Can cost a lot of money! 

Resources:

QGIS is an open-source GIS tool that is compatible with PC’s, Macs and Linux. Try it out here: https://qgis.org/download/ 

Historic Environment Scotland PastMap  

https://www.pastmap.org.uk/ 

Scottish Government Spatial Data www.spatialdata.gov.scot/geonetwork/srv/eng/catalog.search#/home 

Glasgow Open Data Hub  

https://data.glasgow.gov.uk/ 

National Library of Scotland Maps 

https://maps.nls.uk/ 

Historic England Map Database 

https://historicengland.org.uk/listing/the-list/map-search