A Glass Bottom Boat is a motorized watercraft designed to make viewing the undersea environment easy and enjoyable. The most distinctive feature of this type of boat is the large Plexiglas viewing area in the bottom of the boat. This transparent area allows the passengers to view the aquatic life below them as they travel on the water's surface. These unique boats are often used for recreation and can be rented from outfitters. Depending on the size, these ships can accommodate up to 10 passengers. However, smaller models can hold less depending on the restrictions of the local water body. In some cases, glass bottom boats are used as sightseeing tours with a designated tour guide present.