Lake Bolsena

The lake fills a caldera formed by collapsed volcanoes and covers about a hundred and fourteen square kilometres, the largest volcanic lake in Europe, with two islands, Bisentina and Martana, raised by later eruptions inside the crater. In 1263 a Bohemian priest doubting the doctrine of transubstantiation reportedly saw the host bleed onto the altar cloth at Bolsena; the cloth was carried to Orvieto, Urban IV instituted the feast of Corpus Christi the next year, and Orvieto's cathedral was built to house it. Bolsena still lays a carpet of flower petals through its streets for the feast each June.

What you actually see

• The caldera lake - Europe's largest volcanic lake with two inner islands.
• Isola Bisentina - a wooded island with chapels, reopened to visitors in 2022.
• Bolsena's basilica - the church of the 1263 miracle of the bleeding host.
• The Infiorata - streets carpeted in flower petals each June.

When to go

May to September for the water; the Corpus Domini flower carpet falls in June. Island boats run in the warm months only, weather permitting.

Honest expectations

Island access is by seasonal boat with limited sailings and can be cancelled. Shores are dark sand and stone. Towns are small with modest facilities out of season.

Nearby

Viterbo lies south; Orvieto is north in Umbria.