Yeah, same with traveling by boat in the Baltic Sea, been continuously GPS-jammed since 2022 or something annoying like that, basically the entire South East-coast of Sweden been unnavigatable with GPS since then.
> basically the entire South East-coast of Sweden been unnavigatable with GPS since then
This is an interesting first-hand account. If GPS is unreliable, how do you navigate? Perhaps: (1) Only daylight hours and use landmarks? (2) Can modern boat navigation systems estimate your location based upon measured speed and compass direction?
That site has limitations. It uses the GNSS quality send by ADS-B beacons. So, you will only see reliable data if there are sufficient aircraft in that region. But, it is a useful site.