Due to the presence of islands and cliffs, the water in Halong Bay tends to remain relatively calm, without significant waves. As a result, it is generally not common to experience seasickness while cruising in Halong Bay. Most cruise boats also anchor in sheltered areas for overnight stays. However, it’s important to note that during storms or adverse weather conditions, there can be increased wave activity which may lead to a slightly rougher sea. In such cases, cruise operators prioritize passenger safety and may choose to cancel or modify the cruise itinerary.