Spend a night by the River Thames in Greenwich -- 20 minutes by rail from central London -- for up to 51% less than usual. Bed-and-breakfast stays at De Vere Devonport House are now £79, and include a bottle of sparkling wine.

The 4-star hotel occupies a collection of historic former Naval buildings, and is part of the Maritime Greenwich UNESCO World Heritage Site, which includes the Old Royal Naval College, the Royal Observatory and Cutty Sark.