Built in 1867to repel the French navy, the sea fortress Spitbank Fort, located off the south coast of England, has stood immovable for centuries. It has weathered winds, crashing waves and rising tides, housing cannons, muzzle-loading guns and later, breech-loading guns. Today, it houses a circular plunge pool and sauna in its former rooftop gun emplacement, and its ammunition store has been converted into a wine-tasting room.

The historic sea-granite reopened as a luxury spa hotel and retreat in 2012, with eight bedroom suites offering sea views, bar, sunbathing decks, restaurant, and even fire pits.

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The fort-turned-hotel, however, maintains many of its of its original naval features.The , which open so guests can sleep to the soothing sound of the waves, and some rooms evencome with wooden ammunition hoists beside the dressing tables, according to the Financial Times.

Located a mile out to the sea, the fort provides a peaceful getaway for vacationers searching for an island escape.The from nearby Portsmouth and Gosport in Hampshire, according to the Daily Mail. And the luxurious accommodation start even before guests set foot at the fort. Guests are served champagne and canapésat Spitbank's own departure lounge before their private boat transfer.

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"Even though we are only a mile away from land when they come here," Mark Watts, general manager of the hotel, told the Daily Mail.

Exclusive use of the fort (sleeps up to 16) from around $7,690, and individual rooms are available on certain dates from $565 per person.

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