Roadblock

A roadblock is a temporary installation set up to control or block traffic along a road. The reasons for one could be:

Roadworks
Temporary road closure during special events
Police chase
Robbery
Sobriety checkpoint

In peaceful circumstances, they are usually installed by the police or road transport authorities; they are also commonly employed during wars and are usually staffed by heavily armed soldiers in that case. During protests and riots, both police and demonstrators sometimes use roadblocks.^[1]^[2]

Roadblock in the West Bank
Polish barricade during the Warsaw Uprising (1944)
Roadblock during roadworks at Hisingen, Sweden, 2013
'Swarming roadblocks' Extinction Rebellion, (UK) (23 November 2018).

^ Who Approves of Those Who Block Roads to Protest in the Americas? http://www.vanderbilt.edu/lapop/insights/IO921en.pdf
^ Clearing the Path for Land Rights, One Road Block at a Time: How Peru's Indigenous Population can Assert Their Land Rights Against Peru's Government, 1 Global Bus. L. Rev. 229 (2010-2011)

[1] Who Approves of Those Who Block Roads to Protest in the Americas? http://www.vanderbilt.edu/lapop/insights/IO921en.pdf

[2] Clearing the Path for Land Rights, One Road Block at a Time: How Peru's Indigenous Population can Assert Their Land Rights Against Peru's Government, 1 Global Bus. L. Rev. 229 (2010-2011)

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