Map of Devon in SRTM HGT format
A map built from OpenStreetMap data, ready to download
Customize the map
Open this place's area in the constructor and adjust everything to your needs
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What this map contains by default
This is how the map is built as-is — every setting can be changed in the constructor.
.hgt.zip
About SRTM HGT
Map of Devon in SRTM HGT — an export of real OpenStreetMap data for the selected area.
HGT is NASA's native SRTM elevation format: a raw array of 16-bit signed big-endian integers, a strict 1°×1° tile (1201×1201 for SRTM3 or 3601×3601 for SRTM1), no header — programs derive both the grid size and the georeferencing from the FILE NAME, which encodes the south-west corner (e.g. N55E037.hgt). On osm2cdr elevations come from the global Copernicus GLO-30 model (~30 m): the delivery is a ZIP archive holding the full degree tiles covering your area, each named by the SRTM convention. Where there is no coverage (ocean) cells honestly get the void value. The files are read by GDAL, QGIS, OsmAnd, Locus Map.
Which layers are in the file
This file for the selected area contains:
- Roads
- Buildings
- Water
- Greenery
- Points of interest
Coordinate systems
WGS 84 (EPSG:4326), selectable in the wizard
Units
Meters (projected in the chosen coordinate system)
| Category | GIS |
| File extension | .hgt.zip |
| Tier | Open Beta |
How to use SRTM HGT for Devon
- GDAL — gdalinfo -stats N55E037.hgt shows the grid size, the extent and the elevation range: the first check of whether the tile holds real terrain.
- QGIS (free) — drag the .hgt into the window as a raster, then Raster → Analysis → Hillshade or Contour to see the terrain in a familiar form.
- OsmAnd and Locus Map — put the file into the application's terrain folder on the device: the elevation profile will appear in routes offline.
Programs that open SRTM HGT
FAQ: SRTM HGT for Devon
Will the file contain real relief of my city?
Yes: elevations are read from the global Copernicus GLO-30 model at ~30 m resolution — real terrain, not a placeholder. Tiles become flat only where there is no coverage at all (open ocean).
Why do I get a ZIP archive instead of a single .hgt?
HGT georeferencing and grid size are derived from the file name, and a tile must cover exactly 1°×1°. Programs will not open a file with an arbitrary name. So the archive holds full degree tiles with canonical names (N61E147.hgt) — unzip and open them directly, without renaming.
What is the accuracy of the elevations?
Copernicus GLO-30 has a vertical accuracy of roughly 2–4 m (better than classic SRTM) — enough for topomaps, hiking and visualisation, but insufficient for engineering design.
What does the value -32768 mean?
It is the accepted SRTM notation for no data: a point where the radar did not get a valid elevation — often water, steep slopes or radar shadows in the terrain. Most programs show such pixels as empty, and they have to be excluded from calculations.
How do I tell whether I have SRTM1 or SRTM3?
By the grid and file size: 1201x1201 points (about 2.7 MB) is SRTM3 with a step of roughly 90 meters, 3601x3601 (about 25 MB) is SRTM1 with a step of about 30 meters. There is no header in the file, so the version is determined exactly this way.
