Less than 30 miles [48 kilometers] from the hotels and beaches of the overdeveloped Costa del Sol lies Spain's highest, wildest mountain range—and newest national park. The 330 square miles [860 square kilometers] of the Parque Nacional Sierra Nevada, created in 1999, hold 3,000 ibex, 2,000 plant species, and nine peaks higher than 10,000 feet [3,048 meters], including 11,421-foot [3481-meter] Mulhacén, the country's tallest.

The terrain drops from jagged heights to forested gorges and citrus groves; on the sierra's lower slopes is the little-visited Alpujarras region, which has a series of tiny, whitewashed Moorish villages offering trekking supplies, bus connections, and cheap lodging.

Early fall is an ideal time to visit: The weather is cool enough for the lowlands yet warm and dry enough for the high mountains.

All prices in U.S. dollars.

Where to Go
The village of Pampaneira, which sits tucked into the eastern wall of the Poqueira Gorge at 3,500 feet [1,067 meters], is a good starting point for a weeklong backpacking tour up through the valleys and along the crest of the Sierra Nevada.

The staff at the national park visitors center in Pampaneira (Telephone: +34 958 76 31 27) sell maps and can give detailed directions; the trekking route begins right in the main square.

Climbing up the Poqueira Gorge and into oak and poplar forests, the route passes through ravine after ravine as it wends its way eastward, then northward into the sierra. Bridges, churches, and 15th-century Moorish fortresses dot the route, and nights are spent in villages first settled by Berbers.

On the fourth day, you arrive at the highest Alpujarran village, 4,800-foot [1,463-meter] Trevélez. Here, the route heads nearly straight up into the bare, harsh Sierra Nevada wilderness, and on day six you reach the steep domed summit of Mulhacén.

The hike ends two days later and 9,200 feet [2,804 meters] downhill at the lively Alpujarran spa town of Lanjarón, where you can catch a bus out of the mountains.
 

How to Go
In September, Madrid can be reached for as little as $600 from New York and $750 from Los Angeles. Flights to Málaga, much closer than Madrid to the Sierra Nevada, can sometimes be found for the same price.

Search for fares on Travelocity.com and Expedia.com, or try budget-airfare specialists Sunline Travel (+1 212 599 7246) and Moon Travel (+1 212 564 5839). The consolidator AirTech (+1 212 219 7000; www.airtech.com) has frequent last-minute specials to Madrid and Málaga for $189 one way.

The Alpujarras region is accessible by bus; the two-hour ride from the city of Granada to Pampaneira with Alsina Graells (+34 958 18 54 80) costs $3.50. The company also connects Granada to Madrid ($14; five hours), Málaga ($6.50; two hours), and Lanjarón ($2.50; one hour).
 

Lodging and Food
Most Alpujarran villages have small hotels, which typically charge about $20 for a double.

Book ahead at the Hostal Pampaneira ($20; +34 958 76 30 02). Past Trevélez in the high Sierra Nevada, trekkers can find free, often run-down refugios; bring a sleeping bag.

After you summit Mulhacén, you may want to stay the night in the large, modern Refugio Poqueira ($7 per person; +34 958 34 33 49).

Simple meals are about $5 in Alpujarran restaurants; stock up on supplies for the wilderness portion of the trek in Trevélez.
 

Visas and Vaccinations
You can stay visa-free in Spain for 90 days. No vaccinations are required. Contact Spain's tourism office (+1 212 265 8822; www.tourspain.es) for more information.

—McKenzie Funk

Photograph © Tom Bean