There is also evidence, discovered from the air, that throws into doubt the accepted belief that the wall was a barrier between the empire and the barbarian north.

BBC: Tyne & Wear

One of the byelaws prohibits "people climbing on any wall, fence, tree, barrier, railing or structure without a reasonable excuse".

BBC: New laws to combat 'tombstoning' in East Yorkshire

The Berlin Wall once stood as a painful barrier between family and friends, a dark symbol of oppression and stifled liberties.

WHITEHOUSE: Presidential Proclamation -- World Freedom Day

Language was the only barrier, but a friendly smile bulldozed that wall.

NPR: Untold Stories of Kindness

To combat the surge in storms and waves, the government has built what locals call the Great Wall of Male: a concrete barrier 1.8-metre (6 ft) high that partly rings the capital.

ECONOMIST: Letter from Maldives

Sebastian Saavedra hit a tire barrier on lap 33 after Andretti ran him into a wall.

NPR: Conway Wins 1st Of 2 Races At Detroit Grand Prix

The Moroccans used them in the fighting and have now deployed them as their main weapon alongside the 900-mile sand wall, the "Berm" - that they constructed as a barrier between Western Sahara and the Saharawi camps in Algeria.

BBC: News Online

The owner, Veolia Environnement, one of the giants of the industry, has built an underground wall of similarly waterproof clay around the site which extends deep enough to reach the natural barrier below.

ECONOMIST: The charms of modern landfills