Thames barrier rib experience r r leap onboard for the thames rib experience the fastest most exhilarating guided boat tour of london out therer r take in londonandrsquos top landmarks on this interactive guided tour with a difference it takes place on the water at 50 knots more akin to a water rollercoaster ride than a sightseeing cruiser r sights youandrsquoll see include greenwich and o2 arena the thames barrier canary wharf and moreall accompanied by a fascinating fact filled c