File:Swiss GPS reference station SARG (Sargans) (6135699347).jpg

This GPS antenna was set up in 2000 and stands on the former central observation dome of Fort «Furggels» (1206,7 m ASL). It is 1 of 30 GNSS-reference stations in Switzerland of swipos. The automatic GNSS network in Switzerland is operated by the Federal Office of Topography. At the time when the antenna was built, the fortress was still owned by the military and classified. The observers dome was broken off and the hatch concreted over. The massive concrete structure was an ideal foundation for the antenna. The room under the hatch covered with concrete is still accessible from below by a stairway with 179 steps and an iron ladder. At the end of the stairs there is also the turnoff to the fresh air intake and the control of the sliders. The ascent to this point starts inside the fortress left on the way to the water reservoir. St. Margrethenberg, Switzerland, Sep 10, 2011.

New insights Oct 4: The antenna was not built directly on the concrete remains of the fortress, but a little aside. The material under the foundation is not solid rock, and the antenna always moves slightly from time to time. Now a new foundation on rock is under construction. If there is no snow, the antenna is mounted again in October 2011.

New insights Oct 12: The observer dome was not destroyed. The whole upper part was separated and sold to a private person in Mels. If I know where this object is, I'll try to take a photo.