It is bordered on the south by the provinces of Toledo and Cáceres, on the west by Salamanca, on the north by Valladolid, and on the east by Segovia and Madrid.

The northern portion is generally level; the soil is of indifferent quality, strong and marly in a few places, but rocky in all the valleys of the Sierra de Ávila; and the climate alternates from severe cold in winter to extreme heat in summer.

The southern division, however, is one mass of rugged granitic sierras, interspersed with sheltered and well-watered valleys, abounding with rich vegetation.

The ridges which ramify from the Paramera are covered with valuable forests of beeches, oaks and firs, presenting a striking contrast to the bare peaks of the Sierra de Gredos.

Meanwhile, the Adaja, another Douro tributary whose source lies at the cut-off point of the Sierra de Ávila and La Serrota, carries little water in the Summer.