From the time of the Romans until the 18th century there was only one bridge across the Thames. It was quicker and easier to hire water boats to carry travelers from one bank to the other, or up and down the Thames.
Thames travel - A number of boat tours and ferries operate on the Thames. Here are the most useful for visitors.
Catamaran Cruises offer tours with an entertaining commentary, from Embankment Pier to Greenwich. Boats leave every 30 minutes from 1030 to 1715, and cost £6 one way, £8 return. An all-day pass costs only £8.50.
Circular Cruises offer circular cruises from Westminster Pier (Victoria Embankment) as far as St. Katherine's Pier in the Docklands. Cruises depart every 30-40 minutes and cost up to £5.60, with a cheaper option of getting off at London Bridge Pier costing £4. You can also take boats the other direction to Hampton Court, Kew, and Richmond.
City Cruisers offer a range of trips, including service between London Bridge and Westminster Pier, and a Pool of London hop-on, hop-off shuttle. calling at St. Katherine's Pier, Butler's Wharf, HMS Belfast, London Bridge City Pier, and Tower Pier.
Note: with commentaried cruises the crew will pass a hat at the end of the trip and you will be expected to toss in a quid or two as a tip. Be prepared with a handful of change.
Canals and Waterways - The early 19th century saw a proliferation of canals built into and around London, usually for gooods transport. These canals fell out of service as rail transport became a viable option, but now they offfer a relaxing way to travel about the city. For an overview of London canals see the excellent British Waterways site at http://www.british-waterways.co.uk.
Regents Canal travels for 2 1/2 miles through northern London from Little Venice to Camden Lock. On the way it passes London Zoo and Regent's Park. The London Waterbus Company runs enclosed narrowboats from Camden Lock
( Camden Town) and Little Venice ( Warwick Avenue). Boats leave every hour weekdays between 1000 and 1700, and every 30 minutes on weekends. There are a variety of tickets which can also include entry to London Zoo.
Jason's Canal Trips (www.jasons.co.uk) travel the same route in open-sided boats, leaving 60 Blomfield Road in Little Venice at 1030, 1230, and 1430 daily from April to October, with an extra 1630 departure from July-August. There is no 1030 sailing in October.
Jenny Wren (www.walkersquay.com/) offers cruises traveling from Camden Lock, and also operates dinner and Sunday lunch cruises from the Waterside Cafe at 250 Camden High Street. The dinner cruises leave at 2000 Tuesday through Saturday, and last 3 hours. Sunday lunch cruises depart at 1300 and last 2 1/2 hours.
There are also cruises along the River Lea, leaving aboard the Pride of Lea (Tel 7515 8558) from Gillender Street ( Bromley-by-Bow) and including trips to Waltham Abbey, the London Canal Museum (www.canalmuseum.org.uk), or the East Ring Cruise.
British Waterways, the organization which oversees the operation of Britain network of canals and navigable rivers, has a free leaflet called "Explore London's Canals" outlining 6 walks along London's canal towpaths.