Ávila (90km east, 1.5 hours by bus or car). One of the best-preserved walled medieval cities in Europe: the complete circuit of 11th-century walls, with 88 towers, still stands intact and can be walked on top. Ávila is also the birthplace of St Teresa, the 16th-century mystic and reformer; her convents and the cathedral where she was baptised are all within the walls. Regular buses from Salamanca bus station.
Ciudad Rodrigo (90km west, 1 hour by bus). A walled medieval city on the Agueda river close to the Portuguese border, largely off the tourist trail. The cathedral, the castle (now a parador), and the intact circuit of Roman and medieval walls repay a half-day; the weekly market is good for local produce including excellent jamón. Regular buses from Salamanca.
La Alberca (75km south, 1 hour by car). The best-preserved medieval village in the Sierra de Francia: a tight cluster of half-timbered stone houses, cobbled lanes, and an arcaded Plaza Mayor that has barely changed in 500 years. La Alberca is a National Monument and one of the most atmospheric villages in Castile. No direct public transport from Salamanca — a car or taxi is needed.
Valladolid (110km north, 1.5 hours by train). Once Philip II's capital and the most important city in Spain, Valladolid now has an underrated old town and the Museo Nacional de Escultura — the finest collection of polychrome religious sculpture in the world, housed in a stunning plateresque building. Regular Alvia trains from Salamanca.