Ha Long Bay, a stunning UNESCO World Heritage site, is predominantly explored via organized boat tours, ranging from day trips to highly recommended 2-day/1-night or 3-day/2-night cruises, making guided visits essential for a comprehensive experience. Accessibility within the bay is primarily by boat, with some cave excursions involving stairs; individuals with severe mobility issues should inquire about specific arrangements. The most pleasant times to visit are spring (March-April) and autumn (September-November) to avoid the hot, humid summer (June-August) with potential typhoons and the cooler, foggy winter (December-February), though no formal seasonal restrictions apply beyond weather-related cancellations. Costs vary widely, with day trips from $40-$100+ and overnight cruises ranging from $100-$500+ per person, depending on luxury and duration, often including meals and activities. Typical visit durations are 1-3 nights to fully immerse in activities like kayaking, swimming, and cave exploration. Booking cruises in advance is advised, especially during peak season.