Almost 3 miles of original medieval town walls remain around York, more than any other city in England. In the 9th century, invading Vikings buried the original Roman defensive walls, built some 1900 years ago, under earthen ramparts topped with wooden stakes. These in turn were replaced by the current stone walls in the 13th and 14th centuries. In the mid-19th century the walls, which had fallen into disrepair, were restored and maintained for public access, and you can now walk along a narrow paved path at the top and enjoy outstanding views (the whole circuit takes about two hours). In spring, the remains of the Viking embankment at the base are alive with daffodils. The walls are crossed periodically by York's distinctive "bars," or fortified gates: the portcullis on Monk's Bar on Goodramgate is still in working order, and Walmgate Bar in the east is the only gate in England with an intact barbican, although one scarred by the cannonballs during the Civil War. Bootham Bar in Exhibition Square was the defensive bastion for the north road, and Micklegate Bar, in the city's southwest corner, was traditionally the monarch's entrance. To access the path and lookout towers, find a staircase at one of the many breaks in the walls.