Mapping tools have to survive a genuinely awkward set of formats, and most sample data is either a country outline or someone's holiday GPX. Here the same small invented territory (a handful of towns, roads, parcels, and a lake) is published across the formats GIS pipelines actually exchange: GeoJSON and TopoJSON, Esri shapefile component sets (.shp/.shx/.dbf/.prj) and their zipped bundles, KML and KMZ, OGC GeoPackage, GML, and Well-Known Text. GPS coverage spans GPX tracks and routes plus raw NMEA sentence logs. Coordinate-system fixtures pair the same geometry in WGS 84 and a projected CRS so reprojection can be scored against a known answer, and edge cases cover antimeridian crossings, holes in polygons, self-intersections, and empty geometries.
Filter geospatial on Browse · 158 files · 14 subcategories
Results start with a representative from each related test family. Use a card’s variant menu or the filters below to reach a specific format, profile, or failure case; every sample retains its own detail page and download.
Yes. One small invented territory is published as GeoJSON, TopoJSON, shapefile component sets, KML/KMZ, GeoPackage, GML, and WKT, so conversion fidelity can be measured against a known shape.
Coordinate-system fixtures pair the same features in WGS 84 and a projected CRS, with the transform documented in specs, reproject one and diff against the other.
Antimeridian crossings, polygons with holes, self-intersecting rings, empty and null geometries, and mixed-type feature collections, each labelled with what it is meant to break.
Start with one example from each use-case group, then continue through its other test families. Choose a use case, search, or filter to find a specific profile; a card’s variant menu contains its related samples.
39 test families · 158 available files · Page 1 of 3
Crs
A FeatureCollection carrying the `crs` member from the 2008 GeoJSON specification. RFC 7946 removed it and fixed the CRS as WGS 84, so a modern reader should treat this as an ignorable foreign member, but plenty of expor
Geojson
RFC 7946 permits `"geometry": null` for a feature with attributes but no location. Readers that assume every feature has coordinates crash here, and writers that emit an empty Point instead corrupt the record's meaning.
Geojson Edge Cases
The same transect cut at the 180th meridian into a two-part MultiLineString, which is what RFC 7946 section 3.1.9 recommends. The split latitude is the linear interpolation of the unsplit twin, so the two files describe
Geopackage
A GeoPackage holding an `attributes` table with no geometry at all: the standard's own answer to a lookup table you want to ship alongside your layers. Its gpkg_contents row has null bounds and a null SRS, which is what
Gml Osm
GML 2.1 packed coordinates into a single `gml:coordinates` string whose decimal, coordinate and tuple separators are all declared as attributes and can be anything. GML 3 replaced it with `gml:posList`, but WFS 1.0 serve
Gpx
The same eight trackpoints written to the GPX 1.0 schema. The two versions differ in namespace and in where document metadata lives (1.1 wraps it in a `metadata` element, 1.0 puts name, desc and time directly under `gpx`
Kml
Attributes carried in `ExtendedData/Data` elements, which have names and display names but no declared types: every value is a string. Importers must infer that population is a number, and this is where a silently wrong
Nmea
A log with one sentence whose checksum has been altered and a final sentence truncated mid-transmission with no checksum at all: the two ways a serial GPS feed actually degrades. A correct parser drops both and keeps eve
P8 Convert
Real DBF component from the five-town Kestrel Bay shapefile set, copied byte-for-byte into the Convert v2 reserve. Stable P8 artifact p8-convert-shapefile-dbf.
Precision
The same harbour light written to 1 decimal place, enough to identify which country you are in. The ladder exists because coordinate precision is almost always chosen by accident, and shipping six unnecessary digits mult
Shapefile
A zipped shapefile containing a three-file polygon set with no .cpg, so the DBF encoding is undeclared. Zipping is how shapefiles are actually exchanged, because a bare .shp is meaningless without its sidecars, and it is
Territory
Attributes plus a quoted WKT geometry column: the shape PostGIS `COPY`, DuckDB spatial and QGIS delimited-text imports expect. The geometry field contains commas, so it exercises quoted-field parsing as well as geometry
Topojson
The same territory quantized to only 100 steps, so rounding error reaches roughly 220 m and several vertices collapse onto the same grid cell. Use it to prove that a tolerance in your comparison code is actually being ap
Wkt Wkb
PostGIS EWKB, where the SRID is carried by OR-ing 0x20000000 into the geometry-type word and appending the code. A strict OGC WKB reader sees type 0x20000001 instead of 1 and either fails or, worse, reports an unknown ge
Crs
The UTM zone that actually contains the invented territory: zone 28N, central meridian 15 W. It is a definition fixture only: no projected coordinates are published for it here, because a transverse Mercator value is not
Geojson
A top-level Geometry object with no Feature or FeatureCollection around it. This is legal GeoJSON and is what PostGIS `ST_AsGeoJSON` returns, but a surprising number of importers only accept a FeatureCollection.
Geojson Edge Cases
Both rings of the Mill Court parcel are wound the wrong way round: the exterior clockwise, the interior counter-clockwise. RFC 7946 mandates the right-hand rule, and consumers that rely on winding to tell holes from shel
Geopackage
A small raster tile pyramid covering the invented territory, one flat colour per zoom level so a wrongly addressed tile is obvious on sight. The row axis follows the TMS convention, which is flipped relative to the XYZ s
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