Southampton Walls in Southampton, England

A parking lot on top of the medieval walls.

Hidden behind the parking lots, apartment blocks, and shops of this otherwise modern-looking city, medieval walls and ruined towers lurk in a state of frozen decay. These impressive linear defenses once enclosed the entire city, and are some of the most complete, if little-known old city walls in the U.K.

A way-marked trail, "Walk the Southampton Walls" leads curious visitors around the 1.25-mile perimeter of the old medieval trading town. The walk takes in 13 remaining towers, 6 city gates and half a mile of thick stone walls and arcades. Most existing features were built in the 1360s by a population still reeling from an attack by French and Genoese Privateers.

This devastating confrontation in 1338 had seen the settlement's original defensive ditches, wall, and castle fail miserably to defend the population. According to legend, the commander of the attackers, the Pirate Grimaldi, used the Southampton loot to found the Principality of Monaco. The 14th-century walls were the first structures in Britain built to accommodate the newly available defensive technologies of gunpowder and cannon.

The need for the walls had declined by the 18th century and they gradually fell into disrepair and ruin. Today, many of Southampton’s older buildings are built into, onto, or out of these great walls.