A popular way to cruise Ha Long Bay is an overnight stay on a junket boat. They are small and intimate replicas of old ships, and though they do offer short side excursions to caves and floating villages, the experience is really all about drifting the soothing waters of the bay.
Vietnam Travel Tip: We highly recommend this junket experience. There are dozens of cruise lines to choose from, but we ended up on the Jasmine Ha Long Bay. The rooms with balconies were great, and the bathrooms were huge!