To 22 ports; the busiest crossings are to North Greenwich (56 minutes, 54 times a day), Battersea Power Station (19 minutes, 52 times a day), London Bridge (18 minutes, 50 times a day), Canary Wharf (34 minutes, 48 times a day), Bankside (12 minutes, 43 times a day), Tower of London (22 minutes, 43 times a day), Greenwich (47 minutes, 43 times a day) and Westminster (4 minutes, 38 times a day).