Lake Thun

Lake Thun is the larger of the two lakes on either side of Interlaken, 18 km long, with the Bernese Alps rising at its southern end and vineyards on its northern shore.

It has more castles per kilometre than any other Swiss lake, and the boats that connect them are public transport — in the timetable, covered by rail passes. See the lakes.

The castles

Thun — the picture-book keep with four round towers above the town at the western end, now a museum.

Spiez — on a spit closing a crescent bay, with a Romanesque church from about 1000 beside it and vineyards behind.

Oberhofen — the one everyone photographs: a tower standing in the water, with a park running down to it and a Turkish smoking room inside, added by a nineteenth-century owner with ideas.

Hunegg — next door to Oberhofen, and unusual in being preserved exactly as it was furnished in 1900, in Art Nouveau. Nothing has been rearranged.

All four are reachable by boat and are open roughly April to October.

The boats

Scheduled services run the length of the lake between Thun and Interlaken West, calling at the castles and the lakeside villages, taking about two hours end to end.

The fleet includes the Blümlisalp, a paddle steamer of 1906, restored and back in service since 1992. It runs a limited timetable and is worth planning around.

The Beatus caves

On the northern shore, the St. Beatus-Höhlen run about a kilometre into the mountain past underground waterfalls and formations, on a lit walkway.

At the entrance is the cave where St. Beatus, an Irish missionary, is said to have lived in the sixth century after driving out a dragon — the dragon being, as usual in Switzerland, part of the standard package.

Swimming and the shore

The lake is warm enough to swim in from June, and there are public Badis at Thun, Spiez, Oberhofen and Hilterfingen, mostly free.

The northern shore is the sunny side, with vineyards — this is among the highest and most northerly wine country in Switzerland, and the Spiez slopes make a respectable Riesling-Sylvaner.

Above the southern shore, the Niesen funicular climbs a near-perfect pyramid to 2,362 m, with what is claimed to be the longest staircase in the world running beside the track.

Getting there

• By train — Bern to Thun 20 minutes; Interlaken 25 minutes from Spiez; Zurich about an hour and a half.
• By boat — from Interlaken West at one end and Thun at the other.

When to go

May to September, when the boats run at full frequency and the castles are open. The paddle steamer runs a shorter season still, so check its timetable if that is the point of the trip.