Rugged Extremadura a nature lover's paradise, so bring your mountain bike (or plan on renting one), hiking boots, and binoculars. The lush Jerte Valley and the craggy peaks of the Sierra de Gredos mark Upper Extremadura's fertile landscape. South of the Jerte Valley is the historical town of Plasencia and the 15th-century Yuste Monastery. Don't miss medieval Cáceres—boasting one of the best-preserved old towns in Europe—and Mérida with its immaculately preserved Roman amphitheater. Extremadura's other main towns—Badajoz, Trujillo, Olivenza, and Zafra—are charming (if a tad provincial) and virtually tourist-free.