To 17 ports; the busiest crossings are to Woolwich (London) (9 minutes, 26 times a day), Barking Riverside (17 minutes, 26 times a day), North Greenwich (4 minutes, 24 times a day), Greenwich (14 minutes, 24 times a day), Masthouse Terrace (19 minutes, 24 times a day), Surrey Quays (24 minutes, 24 times a day), Canary Wharf (28 minutes, 24 times a day) and Tower of London (40 minutes, 24 times a day).