Lake Tovel

Tovel lies at about eleven hundred metres in the Adamello-Brenta park, ringed by forest and Brenta peaks. Until 1964 the water turned deep red in some summers, caused by a bloom of the alga Tovellia sanguinea; the phenomenon stopped, and long research attributed the change to a decline in nutrients after grazing on the surrounding pastures ended, which removed the nitrogen and phosphorus the alga depended on. The colour has not returned. The lake is now a clear green with a level shore path of about three and a half kilometres. Bathing is prohibited to protect the water.

The landscape

• The clear green water - the lake as it has been since the red bloom ended.
• The story of the red - an alga that stopped blooming after grazing ceased.
• The shore path - a level circuit of about three and a half kilometres.
• The Brenta setting - forest and peaks enclosing the basin.

When to go

June to September; the access road has restrictions and paid parking in peak months, with shuttles at busy times. Snow closes it in winter.

Good to know

The lake no longer turns red and has not since 1964. Bathing is banned. Summer access is regulated with paid parking and possible shuttle-only days.

Nearby

The Val di Non runs east; the Brenta group rises west.

Key facts