Cheisacherturm, Wooden observation tower in Gansingen, Switzerland

The Cheisacherturm is a 25-meter wooden structure built for viewing the surrounding landscape in Gansingen. Its design creates an elevated platform that opens views across the regional countryside in multiple directions.

Around 1830 a large signal stone of the first Swiss triangulation was set on the Cheisacher summit, used by engineer Johannes Eschmann; in 1868 engineer Jacky placed a new Aargau stone there. In 1913 a wooden observation tower eight metres high was built for the canton's triangulation; it was demolished on 11 April 1924, but two concrete foundations remain north of today's tower. In 2005 seven men revived the idea, and the new tower was completed in autumn 2010.

The tower's name comes from the Cheisacher hilltop, and its design project was called «Klus», after the gap formed by two symmetrical elements. Each of the 109 galvanised steel steps carries the name plate of a donor who financed the construction, and the tower was assembled on site in two hours after being flown up in eight helicopter flights.

Wanderwege vom Parkplatz Ampfernhöhe führen in etwa 30 bis 40 Minuten zum Turm. Zur Plattform auf 23,8 Metern Höhe führen 109 feuerverzinkte Treppenstufen, jede mit dem Schild eines Geldspenders. Oben stehen zwei gratis nutzbare Fernrohre bereit.

The tower was flown to the Cheisacher summit by Heliswiss International on 4 October 2010 in eight helicopter flights of about 4.6 tonnes each, then assembled by the Mönthal carpentry firm Bühlmann within two hours. Two concrete foundations of the 1913 surveying tower still stand on its north side.