Osea Island, Essex: A secret so well-kept that even the locals have barely heard of it

Annunciata Elwes looks at a little-known spot accessible for just a few hours a day.

A slice of Nantucket in the enigmatic Blackwater Estuary, Osea Island is a secret so well kept that few of the folk of Essex even know about it.

This is hardly surprising, as the island is approached via a causeway built by the Romans that only emerges from the depths for about four hours a day at low tide.

Osea Island’s Roman Causeway hidden by the waves off the coast of Essex.

Oysters have been harvested here since the Anglo-Saxons were eating them and, although no one lives on the 380-acre island now, visitors can rent a cottage, walk along private beaches, spot wartime pillboxes and birdwatch; as well as sparrowhawks, kestrels and cormorants, Osea is the only place where all five species of British owl can be found.

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