The Brazilian side of the falls and the surrounding rainforest are contained within the Parque Nacional do Iguaçu (tel. 45/3521-4400, www.cataratasdoiguacu.com.br, 8 a.m.–5 p.m. daily Apr.–Nov., 8 a.m.–6 p.m. daily Dec.–Mar., R$12.50), whose entrance, 15 kilometers (9 miles) southwest of downtown Foz, is accessible by bus and car by following the Rodovia das Cataratas. Buses to the “Parque Nacional” leave at 30-minute intervals from the local rodoviária (bus station) in downtown Foz. If driving, you’ll have to leave your car at the main visitor center.

After paying the admission fee, you’ll board a free double-decker bus that departs at 15-minute intervals, traveling along an 11-kilometer (7-mile) road that leads to the Hotel das Cataratas. From here a panoramic 1.5-kilometer (1-mile) trail winds through the forest to various lookout points and catwalks that provide stunning views of the falls.

At the end of the trail at Porto Canoas, is a smaller visitors center, with a souvenir stand, Internet service, and a snack bar. The Restaurante Porto Canoa (tel. 45/3521-4446, noon–4 p.m. daily) serves up a great self-service buffet lunch with terrace tables overlooking the falls.

Many swear that the most breathtaking view of Iguaçu Falls from above. Departing from a heliport next to the Parque das Aves, Helisul (Rodovia das Cataratas Km 16.5, tel. 45/3529-7474, 9 a.m.–5:30 p.m. daily) operates 10-minute helicopter tours for R$140 that fly thrillingly close to the falls.

Another alternative is tackling the falls head on from a boat. Macuco Safari (Rodovia das Cataratas Km 21, tel. 45/3529-6262, www.macucosafari.com.br, R$150) offers an adrenaline-filled foray into the cataracts themselves. The two-hour adventure begins with a guided tour in an electric Jeep, followed by a short hike through the forest to the Rio Iguaçu. After waterproofing yourself and your belongings, you’ll board an inflatable motorboat that sails up the river to the Cachoeira dos Mosqueteiros, where you’ll receive an invigorating bath.

The falls also provide a backdrop to various radical sports. Located within the park (near the Hotel das Cataratas) Cânion Iguaçu (Rodovia das Cataratas Km 27.5, tel. 45/3529-6040, www.campodedesafios.com.br) is an eco-friendly company that organizes outings and provides guides and equipment for adventure sport enthusiasts of all levels and ages. Activities include rock climbing and rappelling, tree-trekking through the forest, and white-water rafting down the Rio Iguaçu.