This gave me a chance to check the coordinates with my android phone, using the GPS status app. This gave me values , which differed by several degrees mainly in latitude.
I verified the values with Googlemaps, and found out, my GPS was matching Googlemaps values.
Two reasons may be the background of the diffence :
- one of the positions is wrong, most probably the one on the monument
- the monument does not show its own location, but something nearby of some importance