Sonnenbergturm, Stone observation tower in Möhlin, Switzerland

The Sonnenbergturm is a 20.8-metre tower of Jura sandstone built in 1913 on the cantonal border between Möhlin and Maisprach. Its covered viewing platform is reached by 99 wooden steps. Inside the tower, architect Franz Koording's construction plans of 5 October 1912 are displayed at a scale of 1:50.

The structure was built in 1913 from local sandstone and replaced an older wooden building from 1875. The original idea came from people associated with the Rheinfelden spa who wanted to create a viewing spot.

The tower is run by the Naturfreunde Möhlin, who have provided a tower keeper since 1951. On Sundays a Swiss flag flying on the roof signals that the Turmstübli annex, built in 1974/75 with voluntary labour, is open. The annex stands entirely in Basel-Landschaft, while the tower itself sits on the cantonal border.

The covered viewing platform is freely accessible; 99 wooden steps lead up to it. Hiking trails from Chlei Sunnenberg take about 25 to 30 minutes. The Turmstübli annex at the foot of the tower, with kitchen and kiosk, is open almost every Sunday, signalled by the Swiss flag flying on the tower roof.

At the platform there is a circular orientation panel system that helps you identify distant places and landscapes. You can use it to spot mountain ranges and forests in the distance and gain perspective on the entire region.