A barricade designed control the flow of vehicular or pedestrian traffic in a specified area.  Commonly used to keep vehicular traffic within the roadway or prevent them from hitting obstacles or running off steep slopes.  They're also used to bar entry, such as on blocking access to incomplete roads and bridges.  Such barriers are also used to protect pedestrians from vehicles, and may be placed to separate areas of high pedestrian traffic from vehicular traffic.

h4. Types

* [[Guard rail]]: 
** Flex-Beam/W-Beam: A long metal W-shaped beam of metal that runs alongside the road.
*** Example: post #5627306, post #6243008
** Thrie Beam: A long metal VVV-shaped beam of metal that runs alongside the road.
*** Example: post #5519007, post #6483822
** Cable barrier: A barrier composed of metal wires affixed to metal poles.
*** Example: post #2616332, 
** Pipe railing: A barrier composed of metal pipes.
*** Example: post #6577813, post #4563235
* Type I, II, & III traffic barricade: Styles of traffic barriers that use 1-3 reflective warning planks/sheets, the type refers to the number used.
** A-frame traffic barricade: A portable wood or plastic barricade made of two A-shaped end pieces and planks with reflective sheeting placed in-between.
*** Example: post #6164622, post #6405555, post #4171864 (Type II)
** Basic Type I-III:  May be portable and kept on t-legs or permanent posts embedded in the ground.
*** Example: post #6034006 (on left: Portable Type II), post #5254303 (Portable Type III)
* Traffic cones and bar: A small rod that affixes between two traffic cones, used to regulate pedestrian traffic .
** Example: post #6459980
* [[Jersey barrier]]: A modular concrete or plastic barrier.
** Example: post #5498800
* Traffic barrel: A large barrel or barrel-shaped portable barrier used as a larger version of a traffic cone to direct traffic or warn of hazards.
** Example: post #5288604, post #6089185
* [[bollard|Traffic bollard]] (barrier poles): Metal or concrete poles used to restrict vehicle access while allowing pedestrian access
** Example: post #5656419, post #554460, post #636645

h4. External links

* "Wikipedia: Traffic Barrier":[https://en.wikipedia.org/wiki/Traffic_barrier]
* "Wikipedia: Jersey barrier":[https://en.wikipedia.org/wiki/Jersey_barrier]
* "Wikipedia: Cable barrier":[https://en.wikipedia.org/wiki/Cable_barrier]