Lac de Serre-Poncon

The dam at Serre-Poncon was finished in 1961 to control the Durance, which had a history of destructive floods, and to generate power and irrigate lower Provence. It is an earth dam about a hundred and twenty-three metres high, and the lake behind it holds around a billion cubic metres across roughly twenty-eight square kilometres. Two villages, Savines and Ubaye, were submerged; Savines was rebuilt above the water. The chapel of Saint-Michel stood on a knoll that is now a low island, or a peninsula when levels drop, and it has become the lake's emblem. The water is a strong turquoise from glacial sediment.

What you actually see

• The Saint-Michel chapel - a lone chapel on an islet in the lake.
• The turquoise water - colour from suspended glacial sediment.
• The dam - a large earth dam with a viewpoint and museum.
• The rebuilt Savines - a 1960s village replacing the drowned one.

When to go

June to September for swimming and water sports; levels are highest in early summer and drawn down through autumn, which changes the shoreline considerably. Winter is cold and quiet.

Honest expectations

Water level varies by many metres through the year, so beaches and the chapel islet look different by season. Winds pick up in the afternoon, which suits sailing and not swimming. Roads around the lake are busy in August.

Nearby

Embrun lies northeast; the Ecrins park is north.