London RIB Voyages

The slick RIB (ridged inflatable boat) operation offers a thrilling, high-speed ride on the Thames. You can book by phone or online or turn up at London Eye Millennium Pier on spec. Arrive 20 minutes before the off to be kitted out with a waterproof jacket, a life jacket and goggle-style visors (fun in itself). The trip starts calmly enough and the guide tends to keep kids and adults entertained with fun facts and celebrity stories. Once the boat gets past Tower Bridge, it really speeds up. The cry goes out: 'Put your hand up if you want us to slow down.' If a small hand shoots up, they steady the boat. The next - 'Hold up a £20 note if you want to go faster' - has imploring young eyes answered with a collective parental 'No'. The boat zigzags excitingly, then turns around by Canary Wharf and speeds back to base. A great way to discover how exhilarating it can be to swoop along the Thames at almost 30 knots, leaving the lumbering traditional river cruisers far behind.