No, you are not required to get off a cruise ship when it docks at a port of call. Many passengers choose to stay on board to enjoy the ship's amenities—such as the pool, spa, or fitness center—while they are significantly less crowded. Staying on the ship can be a great way to have a "relaxing" day without the logistics of excursions. However, there are rare exceptions in certain countries, such as Japan, where local immigration laws may require all passengers to clear customs and immigration in person at the first port of entry. Generally, the ship serves as your floating hotel, and you have the freedom to come and go as you please until the designated "all aboard" time.