Thorney Island, West Sussex: The beauty spot accessed via a secret button through a barbed wire fence

The beaches of Thorney Island, next to Chichester Harbour, are our Secret Britain selection today.

A channel called The Great Deep partially separates the mainland from Thorney Island, part of the watery maze that is Chichester Harbour.

Owned by the MoD, the island played an important part in the Battle of Britain. Now a rather idyllic station for the Royal Artillery, walkers following the Sussex Border Path can gain access by pressing a button at barbed-wire-topped gates and enjoy a nine-mile circular stroll.

You’l spot seals out near Thorney Island.

Surrounded by deserted white-sand and shingle beaches and with mudflats beyond, this peaceful island connects via a sandbank with Pilsey Island (no public access), a habitat for Brent geese, curlews, skylarks, egrets, shelduck and osprey.

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