With a capacity of 14 million kilowatts, this binational dam is the world's second-largest hydroelectric power station, and the one that produces the most electricity per year. The impressive structure, at some 8km long and 200m high, is a memorable sight, especially when the river is high and a vast torrent of overflow water cascades down the spillway. The visitors center is 12km north of Foz. From here, regular tours ( visita panorâmica) depart every 20 minutes between 8:30am to 4:45pm. The more detailed option ( circuito especial; minimum age 14), which takes you into the power plant itself, leaves eight times daily Sunday to Thursday, and 12 times daily on Friday and Saturday. A variety of other attractions within the complex include a museum, wildlife park and river beaches, and a sunset catamaran tour. The project was controversial: it plunged Brazil way into debt and necessitated the large-scale destruction of rainforest and the displacement of 10,000 people. But it cleanly supplies 75% of Paraguay’s energy needs, and 17% of Brazil’s. To get to the Itaipu Dam, catch bus 101 (Vila C Norte-Sohab) or 102 (Vila C Sul-Profilurb), among others (R$3.45, 30 minutes), which leave every 20 to 30 minutes from Foz do Iguaçu's Urban Bus Terminal (TTU).