Ávila

Ávila can be seen in a day: its medieval walls, Spain's best preserved, can be walked along the top in just over an hour, leaving time for the old town inside. April-June avoids both the severe winter cold (Ávila is one of Spain's coldest cities) and summer heat. Prices are low, among the most affordable in Castile and León. Its 11th-century walls, with 88 towers and an almost 2.5km complete perimeter, are the best-preserved medieval walls in all of Europe.