[pierrebeaucamp]

Reminds me of the app from the Swiss federal office of topology (swisstopo), which has the same functionality (albeit limited to Switzerland, of course): https://www.swisstopo.admin.ch/en/swisstopo-application

This webapp seems to be more useful though, thanks for sharing.

[gottheUIblues]

It's topography not topology! Would be funny if a country has a government department dedicated to the mathematical field of topology!