A visit to london is incomplete without a cruise along the thames with a thames sightseeing cruisesall year round the thames london river boat service leaves regularly from westminster pier passing historic and modern places of interest along the river thamesastunning way of seeing all of the major london sights from the river the hop on hop off river pass is valid on both the thames river services and circular cruise services giving you unlimited travel between piers so you can hop o