Founded in the 11th century, this little-known gem is the oldest convent in Madrid province. Noted for its exceptionally well-preserved tower, it nestles idyllically on the richly wooded slopes of La Cabrera Mountain, just 15km (9 miles) south of Buitrago and some 60km (37 miles) from the capital. The most practical way to get there is by hired car, though it's possible to catch the Buitrago bus from Madrid to the village of La Cabrera, at the base of the mountain, and take the steep 45-minute walk up. The trip's well worth the effort, whichever way you make it, as the views from the monastery are superb.