The World Cup has never staged games in a rain forest, much less in the middle of the Amazon. But that is the plan for next summer, an ambition that invites plenty of hurdles. What other major stadium project had to drain an “unwelcome tributary of the French River,” as Neto put it, that ran through its foundation? What other builder has to spend multiple days on each joint that is soldered because the stifling humidity can cause steel to buckle? What other job has to accommodate one of the most ecologically sensitive regions in the world?

Then, of course, there are the concerns about how many more millions will be spent on cost overruns, not to mention what will happen to the stadium once the four World Cup games scheduled to be played here next year are completed. (One recent proposal suggested that the stadium could be converted to a prison.)

Eric Gamboa, an official with the local organizing committee, said the best comparison for the construction of the Arena Amazonia may be to that of the opera house that opened here in 1896.

That construction took place over about 15 years and was financed by the government during a time of booming growth in the rubber industry. The finished product, the Teatro Amazonas, is a gorgeous Renaissance design that, in many ways, looks out of place in its location not far from the city’s more rugged port area.

The stadium project has a similar opulence, and it, too, relies on imported supplies because of a distinct lack of truck-accessible roads to Manaus. Most materials for the stadium have been sent from the port of Aveiro, in Portugal. Three ships were filled with steel and a fourth brought the membrane, or sheath, that serves as the stadium’s partial roof. Each of the ships needed roughly 17 to 20 days to cross the Atlantic Ocean, then navigate the Amazon River and its tributaries to arrive in Manaus.