Urdaibai

Urdaibai is a biosphere reserve in Biscay that surrounds an estuary where freshwater meets the sea and forms wide salt marshes. Oak forests cover the slopes around the bay while steep cliffs line the coast, and the Oka River meanders through the landscape.

The Santimamiñe cave nearby preserves paintings and tools from the Stone Age, showing early human settlement. The United Nations recognized the area as a biosphere reserve in 1984 to protect the wetlands and forests.

The region maintains traditional Basque fishing practices in Bermeo port while sustaining agricultural activities throughout the protected wetlands and surrounding areas.

Several entrances lead into the reserve, with Guernica and Bermeo serving as starting points and observation platforms located along the estuary. The best months for birdwatching are spring and autumn when migratory birds stop over and fill the marshes.

The bay attracts thousands of migratory birds each year, including waders and herons that forage in the shallow waters. At low tide, wide mudflats appear populated by crustaceans and small fish that draw in the birds.

Location: Biscay

Inception: 1989

GPS coordinates: 43.35000,-2.68000

Latest update: December 5, 2025 22:27