17th Century City Walls, Derry City in Northern Ireland

City walls
Derry is the only remaining completely intact walled city in Ireland and one of the finest examples of a walled city in Europe. The walls constitute the largest monument in State care in Northern Ireland and, as the last walled city to be built in Europe, stands as the most complete and spectacular.

The Walls were built during the period 1613–1619 by The Honourable The Irish Society as defences for early 17th century settlers from England and Scotland. The Walls, which are approximately 1 mile (1.6 km) in circumference and which vary in height and width between 3.7 and 10.7 metres (12 and 35 feet), are completely intact and form a walkway around the inner city. They provide a unique promenade to view the layout of the original town which still preserves its Renaissance style street plan. The four original gates to the Walled City are Bishop's Gate, Ferryquay Gate, Butcher Gate and Shipquay Gate. Three further gates were added later, Magazine Gate, Castle Gate and New Gate, making seven gates in total. Historic buildings within the walls include the 1633 Gothic cathedral of St Columb, the Apprentice Boys Memorial Hall and the courthouse.

It is one of the few cities in Europe that never saw its fortifications breached, withstanding several sieges including one in 1689 which lasted 105 days, hence the city's nickname, The Maiden City.