Bollard
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A bollard is an item of street furniture comprising a vertical post fixed into the ground at intervals to prevent vehicle access or to keep vehicles from using the pavement. Bollards can be up to a 1m high but are usually shorter. The intervals between bollards usually allow the passage of pedestrians, prams, cyclists and so on, although they may prevent the passage of trolleys at airports, supermarkets and so on. They can also be used as traffic calming measures to narrow the available space for vehicles to pass through, thereby slowing them down.
With the rise of terrorism in recent years, bollards are more frequently used in city centres to prevent vehicle ramming attacks and ram-raiding.
Bollards are available in various materials (cast iron, steel, concrete, timber, plastic etc), styles and colours and they can also be decorated. Cast iron was a traditional favourite, often with the crest of the city or local authority emblazoned near the top. Plastic bollards (usually red) which sit on the surface are frequently used by highway contractors during road works to separate the worksite from the road. Illuminated bollards can also be seen on traffic islands to provide pedestrian protection and to direct traffic in the desired direction.
The bollard has maritime origins from the time when old cannons were secured (open ends facing upwards and two-thirds buried) into the quaysides to provide a mooring point for ships. When bollards were subsequently purpose-made in the 19th century, they were often designed to have a cannon shape to reference their origins.
Recent years have seen the use of hydraulically-operated rise-and-fall bollards which allow entry at certain times or to certain vehicles e.g fire engines or police cars. When not required, the bollard can be made to descend into a buried housing, leaving its top surface flush with the ground. It is raised as easily when required. A more simple version, often found in car parks, involves a hinged bollard that can be locked in the upright position to prevent access to a parking space, or laid flat on the ground to allow authorised vehicles to park.
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