There's nothing claustrophobic about being inside the walled cities of Segovia and Avila, but the history of each destination is nothing short of fascinating.
Segovia is an ancient walled city topped by the Alcazar, or royal palace. It has a history that dates back to the Romans, the Moors, a Jewish community and medieval Spaniards.
The Walls of Segovia were built after Alfonso VI of León and Castile took the city to the Arabs, who demanded a perimeter of three kilometres, 80 towers and several doors. It was built mainly with granite blocks, but also the reused gravestones of the Roman necropolis.
The Roman aqueduct shows off an amazing feat of engineering, and includes 170 arches made with 25,000 stone blocks held together without mortar. It can be quite confronting to come across this when wandering through the city, as it almost seems out of place. You'll be surprised at how much of it is still standing after almost 2000 years.
Avila's 11th century walls are the most important and best preserved of the Spanish medieval walls. Sitting 1130 metres above sea level, Avila was once conquered by the Moors and then the Christians. Now it sits as a quiet refuge near the Gredos mountains, literally surrounded by massive medieval walls.