The great Rio Guadalquivir rises in the Sierra de Cazorla, amid some of the wildest landscape in Spain, in the Cañada de las Fuentes. For a while, the resulting stream flows confidently north and east, as if it were going to make its way to the Mediterranean. However, the mountains will not let it pass; it meets the Sierra de Segura head on and is forced to make a dramatic change of course, curving suddenly westward to begin its long run down to the Atlantic and the marismas of the Coto Doñana.

At the start of its long march to the sea, the Guadalquivir gives its name to a valley bounded by the sierras of Cazorla, Segura del Pozo and de la Cabrilla: it goes on widening its V-shape toward the south east, confined by a series of peaks that are over 2,000 metres in altitude. The highest peak in this immense area is Cerros de las Empanadas and virtually everything within the boundaries of the reserve is higher than 700 metres, except the land located on the shores of the artificial lake occupying its heartland, the Embalse del Tranco, which is fed by the infant Guadalquivir and its first tributaries.

Innumerable brooks and rivulets pour from the sides of this mountain enclave, and virtually all rush to join the Guadalquivir (except the waters of the nascent Río Guadalentin which eventually flows into the Guadiana Menor). The area has more than 20 rivers and brooks important enough to have names of their own. Beside the main valley of the Gudalquivir, the reserve comprises several adjacent valleys, such as that of Guadalentin and the canyons of Borosa and Aguamala; dramatic narrow cuts in the landscape with steep slopes covered in bushes and pine trees, and high mountain meadows full of succulent grasses and wild flowers - rich pasturelands for herds of sheep. Geologically, the sierra is composed of hard limestone, beneath which lies a softer layer of clays and red sands, they can be seen in section in some of the largest gorges. Its sheltered position between the Montes Universales and the Sierra Nevada means that it was ideally situated to provide a refuge for high altitude plants during the tremendous climatic changes in the Ice Ages. Consequently, these mountains contain a number of Tertiary relict species not found anywhere else in the world. Viola cazorlensis, a shrubby violet with unusual deep crimson or carmine flowers and very long slender spurs, is one of the most interesting. It flowers in May, for the depths of shady rock crevices; its nearest living relatives are found as far away as Mount Olympus in Greece and in Montenegro. Another of these relict species is the bitterroot Piguicula vallisneriifolia. This carnivorous plant is found in a highly specialised habitat under towering limestone cliffs drenched in continually dripping water and totally out of reach of the rays of the sun.

Two endemic species of daffodil also thrive in these mountains - Narcissus longispathus and N. hedaenthus. The latter is a tiny hoop petticoat daffodil found in early May in snow melt areas high in the mountains. A further endemic to this range is the columbine Aquilegia cazorlensis, which is known only from the shady limestone slopes around the summit of Pico de Cabañas and flowers in early June.

All told, the reserve contains over 1,100 species of plants, but you need not be a specialist to enjoy the forests of tall pines that reach 20 metres in height and the sweet profusion of thyme, rosemary, sweet marjoram and lavender. Along the banks of the streams are tunnels of flowers, grasses, ferns and shrubs. The minor rivers are lined with poplars, ash trees and willows. On the lower slopes, the pine forests are made up of Aleppo pine while above about 1,300 metres maritime pine dominates. Here, too, snowy mespilus and Montpellier maple flourish along with such bushes as Lavandula latifolia and Helianthemum croceum. Oaks are also frequent. The high valleys, called navas, are covered with grasses and wild flowers, ideal fodder for the red deer. Some of the mountaintops are treeless, sometimes this is due to natural causes, but more usually, it is because overgrazing has tipped the ecological balance in favour of low growing shrubs rather than trees.

This is a fine camping and hiking area, as well as one of Spain's great nature reserves. You can wake up in the middle of the night to the sound (and smell!) of boars snuffling around outside. This is the spot where you are most likely to discover a herd of red deer in the underbrush. They are not tame and will turn tail at your approach. but encounters are frequent.

Deer watching is easy. If you visit in September or early October you can observe the extraordinary spectacle of the berrea, when the stags stake out both their territorial claims and their harems. Tilting back their heads so that their antlers rest on their backs, they bay to the winds to attract any females within earshot. Sometimes their cry is answered by a challenge and there then follows fierce butting and crashing of antlers until the weaker male gives way.

The animals to be culled are picked very carefully and the effect is virtually that of an integral protected zone. The red deer and roe deer are not easily intimidated by the presence of human intruders. Their visibility varies, however, according tot he season. During the summer, when the days get very hot, especially in the rocky and treeless areas, the animals come out only at night, so you may catch a glimpse of them in the evening or early dawn. In winter, their habits change and with a reasonable amount of discretion, you can come close to them before they run off.

There is plenty of rainfall in this part of Andalusia, particularly during the summer thunderstorms that hurl banks of dark clouds against the perpendicular walls of the high Sierras. The mountains catch the moisture from the Atlantic and the Mediterranean and their effectiveness as a natural barrier is enforced by the thermal masses of warm air from the Levant which usually prevent the Atlantic clouds from moving further east, rain falls in sheets when warm air meets cold air above Cazorla. These periodic inundations are irregular and unpredictable. During the summer, the woods turn to tinder and there are frequent dramatic electrical storms that have often led to major forest fires.

Ubeda

Ubeda (pronounced OO-bay-da), with its wealth of Renaissance palaces and churches, has much in common with its counterpart Baeza.

The outstanding feature is the monumental square, the Plaza de Vázquez de Molina, surrounded with imposing buildings such as the Palacio de las Cadenas (so named for the decorative chains which once hung from the façade). The Capilla del Salvador also has a chapel screen by the ironworker Bartolomé de Jaen. The Hospital de Santiago, designed by Vandelvira in the late 16th century, with its square bell towers and graceful Renaissance courtyard, is now the home of the town's Conference Hall. Ubeda has a Parador, housed in a 16th century palace, which was the residence of a high-ranking churchman of the period.

Both towns, Ubeda and Baeza, have a distinctly Castillian severity, with their granite buildings and plazas, as opposed to the white walls and flower-fill courtyards of Andalusia proper, and in many ways they resemble Segovia and Avila more than Cordoba or Seville. Poetry lovers will be interested to know that the 16th century mystic Saint John of the Cross died in a monastery in Ubeda.

One of the main seasonal attractions of the town is the annual music and dance festival that is held in May and includes opera, jazz, flamenco, chamber music, symphony orchestra and dance.

The nature park of Sierras de Cazorla lays just south east of the town.

Quesada

The town located not far south west of Cazorla.

Cazorla

Cazorlas origins stretch back six centuries before Christ, although the Romans, who named it Carcesa, officially founded it. Its splendour grew under Moorish and then Christian control. Today, the town has a Medieval look about it, and boasts numerous springs, steep, narrow streets and stone houses with balconies full of flowers. There are two well-preserved castles (the Moorish La Yedra and the Christian Cinco Esquinas), both of which are of great historical significance. Testament to the town's former religious importance, five convents can be found amongst the ruins of the Santa María Church.

Close by is the Herrerías bridge which, according to tradition, was built in one night with the aid of Divine Intervention, to enable Queen Isabel the Catholic to pass.

Hornos

Despite some recent construction around the village, the view of Hornos del Segura from afar remains spectacular. The ancient wall of this former Arab fortress stands almost intact, and a castle with tower crowns the village.

Places of interest are the castle and the 16th Century Iglesia (Church) de la Asunción, the latter displaying a fascinating mixture of romantic, gothic and renaissance architecture. There are numerous fantastic viewpoints overlooking the surrounding Natural Park (Parque Natural de las sierras de Cazorla, Segura y Las Villas).

Villaneuva del Arzobispo

The town located not far north east of Villacarrillo towards Beas de Segura.