A lift bridge, also known as a drawbridge, is a type of movable bridge designed to allow water traffic to pass through. Other synonyms for lift bridge include bascule bridge, vertical lift bridge, moveable span bridge, swing bridge, and retractable bridge. These bridges typically have a fixed section on one side and a moveable section on the other side that is lifted or swung open to allow vessels to pass through. The type of lift bridge used varies depending on the size of the waterway and the amount of traffic that passes through it. Each type of lift bridge has its own unique design and mechanism for lifting or swinging the moveable span into place.