A drawbridge or draw-bridge is a type of moveable bridge typically at the entrance to a castle or tower surrounded by a moat. In some forms of English, including American English, the word drawbridge commonly refers to all types of moveable bridges, such as bascule bridges, vertical-lift bridges and swing bridges, but this article concerns the narrower historical definition of the term where the bridge is used in a defensive structure.
A bascule bridge is a moveable bridge with a counterweight that continuously balances a span, or leaf, throughout its upward swing to provide clearance for boat traffic. It may be single- or double-leafed.
The Fremont Bridge is a double-leaf bascule bridge that spans the Fremont Cut in Seattle, Washington. The bridge, which connects Fremont Avenue North and 4th Avenue North, connects the neighborhoods of Fremont and Queen Anne.
The Montlake Bridge is a double-leaf bascule bridge that carries State Route 513 over Seattle's Montlake Cut—part of the Lake Washington Ship Canal—connecting Montlake and the University District.
A moveable bridge, or movable bridge, is a bridge that moves to allow passage for boats or barges. In American English, the term is synonymous with drawbridge, and the latter is the common term, but drawbridge can be limited to the narrower, historical definition used in some other forms of English, in which drawbridge refers to only a specific type of moveable bridge often found in castles.
A tilt bridge is a type of moveable bridge which rotates about fixed endpoints rather than lifting or bending, as with a drawbridge. The tilting Gateshead Millennium Bridge spanning the River Tyne between Gateshead on the south bank and Newcastle upon Tyne, England, on the north is a pedestrian bridge with two large hydraulic rams at each side that tilt the structure back allowing small watercraft to pass under.
A submersible bridge is a type of movable bridge that lowers the bridge deck below the water level to permit waterborne traffic to use the waterway. This differs from a lift bridge or table bridge, which operate by raising the roadway. Two submersible bridges exist across the Corinth Canal in Greece, one at each end, in Isthmia and Corinth. They lower the centre span to 8 metres below water level when they give way to ships crossing the channel.
The Hörn Bridge is a folding bridge in the city of Kiel in the German state of Schleswig-Holstein. The bridge spans the end of the Kiel Fjord and was designed by Gerkan, Marg and Partners.
The Newark Bay Bridge of the Central Railroad of New Jersey (CNJ) was a railroad bridge in New Jersey that connected Elizabethport and Bayonne at the southern end of Newark Bay. Its third and final incarnation was a four-track vertical-lift design that opened in 1926, replacing a bascule bridge from 1904 which superseded the original swing bridge from 1887. The bridge served the main line of the CNJ, carrying daily interstate trains as well as commuter trains.
The Cortland Street Drawbridge over the Chicago River is the original Chicago-style fixed-trunnion bascule bridge, designed by John Ericson and Edward Wilmann. When it opened in 1902, on Chicago's north side, it was the first such bridge built in the United States. The bridge was a major advance in American movable bridge engineering, and was the prototype for over 50 additional bridges in Chicago alone. The bridge was designated as an ASCE Civil Engineering Landmark in 1981, and a Chicago Landmark in 1991.
The George and Cynthia Mitchell Memorial Causeway is a set of causeways in Galveston, Texas, United States. Two of the routes carry the southbound and northbound traffic of Interstate 45, while the original causeway is restricted to rail traffic. It is the main roadway access point to Galveston Island. The second access point is Bolivar Ferry.
The West Jefferson Avenue–Rouge River Bridge is a historic double-leaf bascule bridge in Wayne County, Michigan, at the border of the cities of Detroit and River Rouge. The bridge carries Jefferson Avenue, a major thoroughfare in Southwest Detroit, over the River Rouge, an important inland route for lake freighters. The bridge was built in 1922, and was listed on the National Register of Historic Places in 2000.
Niantic River Bridge, also known as Amtrak Bascule Bridge No. 116.74, is a railroad bridge carrying Amtrak's Northeast Corridor line across the Niantic River between East Lyme and Waterford, Connecticut. It is a drawbridge with a bascule-type draw span. A new bridge was constructed in 2012 to replace the former span built in 1907. It opened on September 8, 2012. Related construction work finished in June 2013.
The Cheboygan Bascule Bridge, also known as the State Street Bridge, is a double-leaf bascule bridge in Cheboygan, Michigan, carrying U.S. Highway 23 across the Cheboygan River. Built in 1940, it was the last bascule bridge constructed in the state of Michigan prior to the end of World War II. It replaced an aging swing bridge built in 1877. The bridge is listed on the National Register of Historic Places.
Eighth Street Bridge is a road bridge over the Passaic River in northeastern New Jersey, United States. It connects the City of Passaic in Passaic County with the Borough of Wallington in Bergen County and is jointly owned by both counties. The bridge connects Eighth Street in Passaic with County Route 507 in Wallington.
The Rio Vista Bridge is a continuous truss span with a vertical-lift bridge in the middle which carries California State Route 12 across the Sacramento River at Rio Vista, California. The present bridge was completed in 1960 and is one of several moveable bridges spanning rivers in the Sacramento–San Joaquin River Delta. It is named after Helen Madere, who served as vice-mayor of Rio Vista. As of 2013 the bridge carries approximately 21,000 cars per day.
The San Leandro Bay Bridge, better known as the Bay Farm Island Bridge, is a single-leaf bascule drawbridge spanning the San Leandro Channel, the inlet of San Leandro Bay within the San Francisco Bay Area, California, United States. It carries California State Route 61 and links the main island of Alameda with Bay Farm Island within the city of Alameda. The present bridge was completed in 1953; it is paralleled by a second bridge devoted to pedestrian and bicycle traffic, the Bay Farm Island Bicycle Bridge.
A double-beam drawbridge, seesaw or folding bridge is a movable bridge. It opens by rotation about a horizontal axis parallel to the water. Historically, the double-beam drawbridge has emerged from the drawbridge. Unlike a drawbridge, a double-beam drawbridge has counterweights, so that opening requires much less energy.
The Mill Basin Bridge is a seven-lane, fixed girder bridge in Brooklyn. It is owned and maintained by the New York City Department of Transportation (NYCDOT) and spans Mill Basin inlet. Completed in February 2019, the span replaces a Bascule bridge originally constructed in 1940. The bridge carries passenger vehicles via the Belt Parkway and pedestrians and cyclists via the Jamaica Bay Greenway.
