GPS receivers are used, for example, as navigation aids, for positioning photos and videos, for locating cell phones or for geocaching. GPS or GNSS receivers enable an exact determination of our position on the earth's surface. Geodetic reference points, such as this one in Kastl at the former train station, are used to check a GPS receiver. ldbv.bayern.de/vermessung/satellitenpositionierung/referenzpunkt/kastl.html