Why Data Is the Foundation of GIS Work
You can have the best GIS software in the world, but without accurate spatial data, your analysis is worthless. The good news is that high-quality, free datasets exist for Nigeria and Africa — you just need to know where to find them.
1. GADM — Administrative Boundaries
GADM (Global Administrative Areas) provides boundary shapefiles for countries, states, and local government areas worldwide. For Nigeria, you can download national, state, and LGA boundaries in SHP or GeoJSON format. Available at gadm.org — free for non-commercial use.
2. OpenStreetMap (OSM) — Roads, Buildings, Land Use
OpenStreetMap is the Wikipedia of maps. For Nigeria, OSM has extensive road networks, building outlines, water features, and points of interest contributed by thousands of volunteers. Download extracts for Nigeria via Geofabrik (download.geofabrik.de) in SHP or PBF format. Completely free.
3. WorldPop — Population Grids
WorldPop provides high-resolution gridded population datasets for all African countries, including Nigeria. Data is available at 100m and 1km resolution and is invaluable for health planning, infrastructure placement, and humanitarian response. Download at worldpop.org.
4. NASA SRTM / ASTER — Elevation Data
Digital Elevation Models (DEMs) are essential for terrain analysis, watershed modelling, and flood mapping. NASA's SRTM provides 30m-resolution elevation data globally. Download through USGS EarthExplorer (earthexplorer.usgs.gov) — free after a simple registration.
5. Copernicus Land Service — Land Use / Land Cover
The European Union's Copernicus programme releases annual land cover maps for Africa through the Copernicus Global Land Service. Categories include cropland, forest, urban, water, and grassland at 100m resolution. Available free at land.copernicus.eu. Excellent for change detection and environmental monitoring.
Getting Help With Your Data
If you need to process, analyse, or visualise any of these datasets for a project, CLEVERRISH GLOBALS offers GIS analysis services and training to help you get from raw data to actionable outputs. Contact us to discuss your project.