Hadrian's Wall, built nearly 2000 years ago by the Romans during the reign of Emperor Hadrian, was a cleverly-designed military rampart manned by 20,000 troops. This 73-mile long undulating wall likely defined and protected the bleak northern edge of Roman Britain from pesky barbarians. Much-loved by hikers and historians, the wall is truly one of England’s most thought provoking sights. For more information on the Rick Steves' Europe TV series — including episode descriptions, scripts, participating stations, travel information on destinations and more — visit www.ricksteves.com.