4. Gugh, Isles of Scilly, Cornwall

From the pier on the isle of St Agnes, pass the tempting Turk’s Head – Britain’s most south-westerly pub – and head along a narrow lane and sandy track. If the tide is out, a bar of sand joining St Agnes to Gugh will swing into view. This link between the two islands is a tombolo, a natural phenomenon that is rather rare in Britain.

Your first encounter on Gugh is with the 90-acre island’s two houses, built a hundred years ago with extraordinary curving roofs to withstand the Atlantic gales. An anticlockwise ramble from here will take you back centuries and then millennia. At Gugh’s southern end, the Carn of Works Civil War battery is guarded nowadays by lesser blackbacked gulls rather than Cavaliers. Turn north and you’ll meet the Old Man of Gugh, a 9-foot high Bronze Age leaning menhir (standing stone). Then climb Kittern Hill with its entrance graves and the remains of round houses and kelp pits. From the summit, a wondrous panorama awaits you: several Scillonian islands, the Western Rocks – scene of many a tragic shipwreck – and the slender finger of Bishop Rock lighthouse.