SRTM (Shuttle Radar Topography Mission) is an international project that collected topographic data over nearly 80% of Earth's land surfaces (excluding Polar regions), creating the first-ever near-global dataset of land elevations.
The model has three versions: the most detailed, at 30m resolution, was released in 2013.
The project is led by the U.S. National Geospatial-Intelligence Agency (NGA), and NASA.