The Bisses of Valais – Botyre (Ayent), Switzerland - Atlas Obscura
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Botyre (Ayent), Switzerland

The Bisses of Valais

Medieval irrigation channels built into the sides of mountains provided Valais with water for hundreds of years.  

Some of the best places to hike in the state of Valais in Switzerland are ancient pathways that once used to bring water down from mountain streams to farms in the valleys and meadows below.

The creation of these channels, known as bisses, goes back at least as far as the 14th century, though some believe those medieval routes were built where Roman channels had previously been. In the aftermath of the Black Death in the mid-1300s, with a significantly reduced population across Europe, the grain fields in Valais were repurposed to grow hay to raise cattle for the rising demand of beef across the border in Italy.

Owners of the fields and pastures pooled their resources to build bisses for irrigation, which was more necessary than it had been for growing grain. A lot of resources were needed, since many of the bisses were built into the sides of mountains and cliffs, which made digging them particularly dangerous hundreds of years ago. They tended to be between 5 and 10 kilometers, though a few stretched more than 20 kilometers.

Over time, they came to be used by vineyards and orchards in the area as well. Those more wealthy landowners, who controlled the water supply, arranged for systems allowing the use of the water by the smaller farmers. The smaller farmers and their families, in turn, helped maintain the bisses, cleaning and repairing them every spring. Canal guards, who lived in cabins along the channels, kept regular watch over the flow of water, making sure it was not interrupted.

For the most part, the bisses that remain have become scenic tourist attractions and inspired hiking trails, though some are still in use. Some of the trails run alongside the bisses, but others are the bisses themselves, repaired and reinforced. Le Musée des Bisses offers a convenient itinerary of some of the most spectacular bisse-adjacent trails, the bisse of Sion, the bisse ‘Ayent, and the Bitailla, in addition to exhibits on the history of the Valais bisses.

The address and coordinates above are for the museum, which provides a good launching point for many hikes through the bisses.