Lan Ha Bay and Halong Bay are both excellent choices, but they offer slightly different experiences. Choose Halong Bay if you are visiting for the first time and want to see famous landmarks such as Sung Sot Cave, Titop Island, and Luon Cave. It offers a wider selection of cruises, from traditional junks to luxury vessels. Choose Lan Ha Bay if you prefer a quieter atmosphere, beautiful limestone scenery, kayaking, swimming, and a more relaxing journey.