Filso

Filso was once among the largest lakes in Denmark before it was drained in stages from the 1850s for farmland, and in 2012 a foundation bought the land and reversed the work, breaking the drainage and letting the water back in, creating around nine hundred hectares of shallow lake, reed and wet meadow. The response was rapid: within a few seasons it had become one of the most productive bird sites in Denmark, with breeding avocets, black-necked grebes and marsh harriers, very large autumn gatherings of geese and ducks, cranes, and regular sea eagles. There are hides, viewing points, a tower and paths, and the surrounding heath and plantation are part of the same reserve. It is a rare example of a large-scale reversal being carried out and working.

What's there

• A re-flooded lake - nine hundred hectares returned to water in 2012.
• Breeding avocets and grebes - species that colonised within a few seasons.
• Autumn goose and duck flocks - large numbers on the open water.
• Hides and a viewing tower - the access points around the shore.

When to go

April to June for breeding birds, September to November for geese and passage. Half a day. Dawn and dusk are the productive hours. Winter brings raptors and wildfowl.

Before you go

It is a bird site and offers little to anyone not interested in birds. A telescope makes a large difference. There is no visitor centre. The paths are exposed with no shelter. Mosquitoes are bad in summer.

Nearby

Blavand and the coast are south-west; Varde lies east.

Key facts