On 27 July 1999, 21 people between the ages of 18 and 31 were killed by a flash flood in Saxetenbach Gorge in Interlaken, Switzerland. Forty-four travellers and eight guides were canyoning as part of an organised tour when storms caused flash flooding of a mountain stream within the gorge. Reportedly, there was natural made log jam or dam at the top of the ravine that gave in due to storm waters, causing a tidal wave approximately 10 – 15 ft tall that overwhelmed the canyoners.

Among the 21 dead were 14 Australians, two Swiss, two New Zealanders, two South Africans and one Briton.

Preliminary investigations indicated that the tour guides did not heed weather warnings before the flood event occurred. In December 2001, six members of the company which conducted the canyoning excursion were found guilty of manslaughter by culpable negligence.