Tattershall Castle

In terms of floating bars, the Thames is something of a missed opportunity, but once you get your sea legs, this 1930s’ paddle steamer is a ship-shape alternative to landlubber lounges. Its all-weather decks work best on fine days when, for the price of a classic cocktail (at £7.95), the historic views are at their finest; you can also sip a glass of wine, a bottle of craft lager or knock bag a shot of something stronger while you admire the scene. Food includes a range of mezze platters, sandwiches, burgers, salads and mains such as pancetta and leek carbonara, steak and ale pie or baked whole seabass, with a small but well chosen selection of puds to follow. There’s a daily barbecue throughout summer, plus weekly salsa classes, a weekend disco and a comedy club for those drawn to messing about on the river.