OgleEarth posts about Hey, What’s That?, a website that lets you enter a location and then gives you:
- A panorama of what’s visible from that location, marking the position of peak geographic landmarks
- A list of the peaks, and the ability to show their position relative to your location on Google Maps
- Terrain profiles (elevation versus distance from the location to any point on the map)
- A plot all the areas visible from that location in red on Google Maps (aka the “viewshed” or “weapons fan”)
- Contour lines (zoom in for these)
- Google Earth export of position, viewshed, horizon line and horizon extent. If the viewshed area is large, this might strain the memory capacity of lesser systems.
It uses 30-meter SRTM version 1 data for its calculations, so there may be some quirks depending on whether there are holes in the SRTM coverage for your area. They’re switching over to SRTM version 2 soon, which is better but still not perfect. It only works in the US right now, but according to OgleEarth, they hope to expand coverage worldwide. A cool site! Check the OgleEarth posting for more info.