Beacon in the film 'Return of the King', the third instalment of the 'Lord of the Rings' trilogy. YouTube

Watchtowers, the alarm system of the Old Swiss Confederacy

Whereas sirens sound the alarm nowadays, hundreds of years ago it used to be watchtowers. Beacons could mobilise troops within a few hours, from the Rhine to Lake Geneva.

Thomas Weibel

Thomas Weibel

Thomas Weibel is a journalist and Professor of Media Engineering at the Fachhochschule Graubünden and the Hochschule der Künste in Berne.

Aragorn rushes breathlessly into the Hall of the King of Rohan: “The beacons of Minas Tirith, the beacons are lit! Gondor calls for aid!” Everyone turns round and King Théoden responds grimly: “And Rohan will answer! Muster the Rohirrim!” The fantasy world of 'Lord of the Rings' penned by British author J. R. R. Tolkien is riven by battles between good and evil. After this scene in the last instalment of the trilogy, Théoden gathers his warriors together. Tolkien was more than just an author of fantasy; he was first and foremost a medievalist and linguist. He also knew all about watchtowers and how they were used to sound the alarm over long distances in the late Middle Ages.
In the olden days, Confederation troops were mobilised by mountaintop beacons. One beacon was lit, the fire was seen by the next watchtower, which in turn lit a beacon for the next tower and so on. The alarm thus travelled across the entire network – in the canton of Vaud, the summits where the watchtowers were located are still known as 'signal'. These networks were extensive in the 17th and 18th centuries and could stretch over hundreds of kilometres – the canton of Lucerne had 17 beacons, Zurich 23, Fribourg 33, Thurgau 51, and the network of 156 watchtowers known as 'Chutzen' in the canton of Bern extended from the Rhine to Lake Geneva. The significance of the beacons lives on today in the names of mountains and plateaus, for example 'Pfannenstiel' or 'Wachthubel'; the name 'Hochwacht' (watchtower) can be found in the cantons of Bern, Aargau, Lucerne, Zug, Zurich, Thurgau, St. Gallen and Appenzell Ausserrhoden.
Watchtower map for the Canton of Zurich, 17th century.
Watchtower map for the Canton of Zurich, 17th century. Zentralbibliothek Zürich
Watchtowers are among mankind’s oldest military installations; they helped the cantons secure their territory in times of war. Early beacons took the form of a tree visible from far away with straw and brushwood placed around it, which was set on fire. In later times, watchtowers formed a pyramid of up to 20 metres high comprising three or four pine trees planted in the ground at six-metre intervals. A wooden base at head height connected the trees and supported a woodpile going up to the top. A pit in the middle served as a vent; the wood was enough to keep the beacon burning for at least an hour and a straw roof kept the wood dry.
From the 15th century, the watchtowers, which were normally at a maximum of 1,500 metres above sea level, provided a sophisticated alarm system. They consisted of a manned hut or tower, an orientation instrument known as a 'Richtdünkel' to determine the precise location of the next beacon (to avoid confusing a beacon with a normal blaze), a tilting pot with resin or pitch hanging from a gallows-shaped structure, a cannon and dry wood. At night, signals were sent by fire, during the day by smoke and in fog by cannon blast, as attested to by Zurich military engineer Johannes Haller in his work Defensional from 1620.
Watchtower, reconstruction.
Watchtower, reconstruction. Department of education, Canton of Bern/Municipality of Ringgenberg
The municipality where the watchtower was located normally managed the building and maintenance work, and provided the guards. They were expected to conduct themselves with decorum and restraint, especially when smoking and they were responsible for defending the watchtower. If the Council in Bern issued a declaration of war, the guards on the cathedral tower circled the upper terrace five times carrying flares. Then cannons placed on towers along the city wall fired three times and the church bells began ringing loudly. The watchtowers lit up on the Gurten, Bantiger and Harzerenhubel mountains as the message relayed all the way down the line. Bernese author Rudolf von Tavel brings this scene to life in his novel 'Ring i der Chetti' published in 1931, when he compared the fires lighting up in succession to a constellation of red stars.
Speed is the key to victory in wartime. Assuming it took ten minutes to light up a beacon, a signal could travel from Bern to Zurzach on the German border  in a total time of three hours. From Bern to Geneva, it took two-and-a-half hours, and one hour 40 minutes from Bern to Guttannen. Church bells and drums spread the alarm in the towns and villages. So, the entire territory of the old canton of Bern could be warned within three hours, and the troops ready to mobilise in five hours.
Genevan soldiers being called to the border in 1871.
Genevan soldiers being called to the border in 1871. VBS/DDPS - Albert von Escher
The last time beacons were used was in 1870 during the Franco-Prussian war, when the Federal Council called up five battalions totalling 37,000 troops to secure the border crossings from Schaffhausen to Pruntruter Zipfel. Nowadays, the watchtowers can be used as measurement points for land surveys – as well as popular hiking destinations because of the views.
Albis watchtower, 1935, photo by Leo Wehrli.
Albis watchtower, 1935, photo by Leo Wehrli. ETH Library Zurich

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