Express boats service Phnom Penh from Siem Reap and boats leave from south of the Japanese Bridge on Sisowath Quay at Street 104. Tickets are sold at the dock and should be bought at least one day in advance. This is quite an adventurous way to get to Siem Reap and occasionally these local ferries break down or become grounded if the water is too low or the service is suspended. The best time to travel is during and just after the rainy season, so June to November. There is a regular boat service between Phnom Penh and Chau Doc on the Mekong in Vietnam, with several operators including Blue Cruiser (tel: (023) 990 441; website: www.bluecruiser.com) and Hang Chau Boat Company (tel: (012) 883 542). Taxis and motodops (motorbike taxis) always meet the boats.