During the installation of a node and the inspection for further investigations, we were at the Sonnblick for some time. The video (https://www.linkedin.com/feed/update/urn:li:activity:7109893386802712576) shows the impressive rock massif on which the observatory is located and also gives an impression of the location (in splendid weather). This readable newspaper article also gives an excellent insight into the history of the observatory.
Due to its exposed location, the observatory can be used for interference-free measurements. Images, data (also long time series), photos and 3-D models can be viewed at https://www.sonnblick.net/de/das-observatorium/. Highly recommended.