In some places, residents and paramilitaries built barricades to seal off and protect their neighbourhoods from incursions by "the other side", the security forces or both.

By the end of 1971, 29 barricades were in place to block access to what was known as Free Derry, 16 of them impassable even to the British Army's one-ton armoured vehicles.

The tanks had been transported to Northern Ireland on board the amphibious landing ship HMS Fearless, and were operated with their turrets traversed to the rear and main guns covered by tarpaulins.

[9] The British Army used bulldozers and Centurion AVREs to break through the barricades before flooding the no-go areas with troops in smaller, lighter armoured vehicles.

[11] RAF Canberra reconnaissance aircraft were employed to search for arms dumps through false colour imaging.

[12] By the end of the day, Derry and Belfast had been cleared of no-go areas, but the Army remained cautious when operating in staunchly republican districts.

Casement Park in Andersonstown, the main stadium of the Ulster GAA, was occupied by 19th Regiment Royal Artillery;[13] it was returned in 1973/4.