Overview
The Sierras de Cazorla, Segura and las Villas Natural Park covers over 200,000 hectares and is one of the largest Natural Parks in Spain.  Located in eastern Jaen province, it connects the Sierra Morena and the Subbética mountain ranges.  This huge mountainous natural park is home to widespread forest, dramatic, dominating peaks reaching up to over 2,000 metres and numerous rivers, steams and waterfalls.  It is rich with diverse flora and fauna with many endemic species. 

The park is contiguous with the Sierra de Castril Natural Park which forms its south eastern border.

Walking
There are two visitors' centres, the Centro de Visitantes Torre del Vinagre and the Centro de Interpretación Fluvial Río Borosa.  Both have exhibitions on the park's flora and fauna and can provide maps and information on walks and accommodation.  The park is very popular with campers and hikers, particularly during holiday times.  Weekends, Easter and between July and August are probably the busiest and should be avoided if possible.

The park is immense, but there are only 7 are sign-posted trails.  The rest you’ll need a good map and compass to follow.
Sendero Río Borosa is a long (18km) route and probably the park's most well known.  This leads the hiker through a magnificent gorge, passing waterfalls on the way upstream to two mountain lakes.

Sendero Cerrada de Utrero is a much shorter route (only 2km) which takes the visitor through a gorge to a beautiful waterfall.

Sightseeing
There are several remains of castles within the park.  One is at Tranco de Beas reservoir, which has the remains of a small Castle of San Miguel de Bujaraiza. There are Arab and Christian Castles at Cazorla. The Templar Castle and the Tiscar viewpoint.

The Sierras de Cazorla, Segura and las Villas Natural Park is home to some magnificent waterfalls, like those of the Salto de los Órganos and the Cascada de Linarejos, and sheer-sided gorges, such as the Cerrada de Utrero and the Cerrada de la Canaliega.  Due to the limestone nature of its mountains the park has many caves and is popular with cavers/pot-holers.  Cueva del Agua is one such cave, although this is more accessible to the general public as it is occasionally used to hold music concerts because of its natural acoustics!  Cueva del Peinero is another beautiful cave located near Villacarrillo in the Sierra de las Villas. 

Sierra de Quesada, near the town of the same name, is one of Andalucia's most important areas of prehistoric cave paintings, which can be found in the Abrigo del Cerro de Vitar, south of the town. Also in this Sierra are the Cueva de Encarejo and the Cueva de Hiedra.

The village Hornos is particularly worth visiting just for its location.  It is balanced on a rocky crag along the Segura de la Sierra, providing stunning views over the Tranco reservoir.

Animals/Birds
The park is a rich haven for wildlife.  High in the mountains are the raptors.  29 species have been recorded; these include golden, short-toed, booted and Bonelli’s eagles, Egyptian and griffon vultures, red kites and goshawks among others.  Smaller birds include kingfishers, great tits, coal tits, woodpeckers and short toe creepers to name but a few. 

Mammals that inhabit there area Spanish Ibex, several species of deer, otters, polecats, wild boar, genets, stone martens and foxes.  There is a small reptile that lives between the cracks in the rocks: the wall lizard of Valverde, discovered in 1958, a species that can only be found in this area. There are also unique insects and the rivers and streams are teeming with trout, carp, barbell and black perch.  

Plants
Over 13,000 species have been recorded and twenty four of them are exclusive to the area. The Sierra de las Empanandas, Sierra de las Cabrillas, Sierra del Pozo and the Sierra de Segura are where the flora is at its most exceptional.  Much of the park is covered in pine forest, some of which is estimated to be over 1,300 years old.  In the Sierra de Cazorla you can find nearly 100 of these ancient laricio trees and also the Pino Galapán which is a pine tree which measures 5m around the trunk and 35m high.

The Sierras de Cazorla, Segura and las Villas Natural Park is also home to one of the smallest narcissus in the Iberian peninsula – narcissus hedaenthus, found only in the high mountains around May in snow melt areas. Mediterranean herbs such as thyme, rosemary, marjoram and lavender all thrive here.  A little of the original Mediterranean woodland still exists; Sierra de Seguara has a few examples of ancient gall and holm oaks.  In Springtime the park is covered in wildflowers.