Covering some 76,080 hectares (188,000 acres), Cota de Doñana National Park is Spain's largest wildlife reserve and one of the continent's last great wildernesses. At an estuary of the River Guadalquivir, it is also one of the world's greatest wetland sites for migrating birds. Bird-watchers by the thousands flock here in spring when hundreds of flocks of breeding birds fly in to nest in the wetlands. In all, there are 300 different species of rare birds, along with colonies of storks, buzzards, kites, kestrels, and egrets, plus 33 species of mammals, 12 species of fish, and 18 species of reptiles. There have even been sightings of the almost-extinct Spanish imperial eagle.

Mammals on the verge of extinction, including a rare lynx, also live here. Wild boar can be seen in the marismas (swamps).

The park is also the home of more than 10 separate kinds of orange, tangerine, and citrus trees, an estimated 300,000 trees in total, many of them cultivated on the park hotel's sprawling, 1,000-hectare (2,471-acre) farmlands. (The hotel is reviewed below.) Thanks to the efforts of the local government, the park is also the site of an aggressive reforestation program.

The best bird-watching base is the village of El Rocío on the northwestern edge of the marshes. The enveloping marshes and pinewoods here teem with honking wild geese and white storks. The Doñana Visitor Center is at La Rocina (tel. 95-943-96-27), less than 2km (1 mile) west of El Rocío. A footpath has been cut through the wetlands here, and you can walk its 3.5km (2 miles) daily from 9am to 2pm and 3 to 9pm. Free maps are provided. Along the way you might encounter such creatures as the red-crested pochard or the magnificent hoopoe, even flamingos and hundreds of singing nightingales.

There's another information center at El Palacio de Acebrón (tel. 95-950-61-62), 5km (3 miles) to the west and with the same hours. This former hunting lodge has an exhibition tracing the history of the park. Bring a picnic as this is an ideal spot for lunch.

From La Rocina, a drive of 9km (5 1/2 miles) will take you west to the Centro Recepción del Acebuche (tel. 95-943-04-32), the park's main interpretive center. It's open daily June to September from 8am to 9pm; October to May daily 8am to 7pm. Jeep tours, which must be reserved in advance, depart from here hourly, cost 25€ ($40) per person, and last 4 hours. These tours take you through an area of the park stretching for 70km (43 miles) across scrubland, sand dunes, salt marshes, and beaches. Bring a pair of binoculars. In summer most of the birds disappear when the marshes dry up. In their place you'll see grazing horses and deer.

To reach Acebuche, drive 12km (7 1/2 miles) south on the A-483 from El Rocío, and then go for 1.6km (1 mile) west (it's signposted). At Acebuche there are footpaths to bird-watching sites overlooking the lagoon.