The southern extension of Ha Long Bay, separated from the main heritage zone by Cat Ba Island. Lan Ha contains around 400 islands across roughly 70 square kilometres of sheltered water, with the same dramatic karst formations as Ha Long but a fraction of the tourist boats.
Cruises out of Cat Ba town typically spend their time in Lan Ha rather than crossing into the more crowded heritage zone. Highlights include the small white-sand beaches of Ba Trai Dao, the calm kayaking conditions around Tra Bau, and the floating fish farms of Cai Beo — one of the oldest continuously inhabited sites in coastal Vietnam, with archaeological evidence of settlement going back 7,000 years. For travellers who want the Ha Long landscape without the cruise-industry scrum, Lan Ha out of Cat Ba is the better option.