10 best secret islands

For wild camping

Shell Island, Gwynedd

OK, this is more of a peninsula than an island but twice a day every other week, tides cover the causeway across the river estuary and no cars can drive across. The best way to enjoy Shell Island is to pitch a tent - there are 300 acres of wild camping available - and wake up to the soul-stirring views of Cardigan Bay and the mountains of Snowdonia. Laze away the days on one of the sandy bathing beaches and gather your own seafood supper of crabs, mussels and clams to savour in front of your campfire as the sun sets (www.shellisland.co.uk).