Traditional use of the term "rolling bridge" dates from at least the Victorian era, and is used to describe a type of retractable drawbridge used to span a ditch or moat surrounding a fortification. That type of bridge is not hinged, and remains horizontal when it is rolled inside the gates of a fort.[4] Modern versions are called retractable bridges or thrust bridges. One particular version of the rolling bridge type was known as the Guthrie rolling bridge, examples of which may still be seen at Fort Nelson, Portsmouth. Certain types of bascule bridges roll on an arc; an example is the Pegasus Bridge.
Coordinates: 51°31′06″N 0°10′29″W / 51.518390°N 0.174735°W