View from Lauchernalp in E direction to Bietschhorn (3934 m). The load of frequent rock falls from Kleines Nesthorn (3342 m), just in font of Bietschhorn, onto Birchgletscher on the left side had accelerated and destabilized the glacier, which finally collapsed on 28 May 2025. The resulting avalanche of roughly 10 million cubic metres of ice and rock buried the village of Blatten, which had been evacuated before, and, due to its high mobility, also part of the valley downstream.