Pick a structure location and height, add a DTM or DSM, and the model works out where a viewer at 1.5 m eye height could see the top of the structure within your study radius, allowing for earth curvature and refraction (GDAL Viewshed). It reports the visible area in hectares, the visible area and percent visible in each distance band, and, if you tick the option, downloads OpenStreetMap buildings and lists those that can see the structure with their distance to it. A DTM gives the worst-case bare-earth ZTV; a DSM includes screening by existing buildings and trees. One structure per run; the README shows how to run several as a batch and add them up to count how many each place can see.
Eight Bozmaps QGIS models in one zip: flood, landslide, wildfire, NDVI, NDVI change detection, land surface temperature, OSM map generator and vegetation vulnerability.
Screens how far inland a tsunami of a height you choose could reach, from a DEM, a coastline and land use roughness, using the published Berryman height-loss method.
5, 10 and 15 minute walking catchments along the OpenStreetMap street and path network from any number of points, with building counts per band.