At 2'262 metres, the Chäserrugg is the easternmost summit of the Churfirsten and the only one in the chain served by a railway. From the broad summit plateau in the canton of St. Gallen, the view drops almost vertically south to the Walensee, north across the Toggenburg and, in clear conditions, as far as six countries.

The summit is crowned by a timber building by Herzog & de Meuron that unites the mountain station and restaurant under a far-projecting roof and is a destination in its own right. Trails lead from the plateau to the neighbouring Hinterrugg and down via the Alp Sellamatt into the valley; in winter the Chäserrugg is the gateway to one of eastern Switzerland's most snow-sure ski areas. Sunrise trips and full-moon dinners are part of the summit restaurant's programme.

The Chäserrugg is reached from Unterwasser by the summit railway via the intermediate station Iltios. Unterwasser is served by PostBus from Nesslau-Neu St. Johann in around 15 minutes, and Nesslau by train from Wil in around 45 minutes. By car, drive from Zurich via Wil into the Upper Toggenburg. Tickets: chaeserrugg.ch