roadblock

thumb|Concrete barrier 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 Protests

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.