By Sarah Andrews

Parque Natural de la Sierra y los Cañones de Guara is one of the most spectacular and least exploited of Spain's 13 parks and thousands of nature reserves. Offering everything from canyoning and renowned climbing to cultural monuments like prehistoric cave art, the Parque Natural is a wonderland.

Spain's protected areas total 6 percent of the country's land, and visitors can travel easily from park to park. Refugios throughout the countryside offer cheap lodging and meals.

While any one of Spain's parks is worth visiting, a few stand out. The Parque Nacional de Aigüestortes i Estany de Sant Maurici in the northern Catalan Pyrenees has more than 200 mountain lakes. The towns and ruins scattered throughout the park make for great mid-trail stops.

To the south, the dry, barren peaks of Granada's Parque Nacional Sierra Navarra, where trekkers hike in the company of wild mountain goats, protects more than 2,000 plant species, 66 of which are not found outside its borders. Further south, Andalucia's Parque Nacional de Doñana is a highly-regulated wildlife preserve, protecting the thousands of birds that migrate between Africa and Europe each year. Guides will accompany you into the interior of the park to see rare eagles and other wildlife.

For more information about Spain's protected natural areas and for links to its national parks log onto www.mma.es.