When most people hear the name “Foz do Iguaçu,” their minds immediately drift to the thundering, majestic Iguaçu waterfalls that gave the town its name. If not the falls, you’ve probably heard of the Triple Frontier, the unique spot where the borders of Argentina, Brazil, and Paraguay meet. But during my time in this little town, I discovered there is one more colossal sight that visitors can see here, one that doesn’t quite get the limelight it deserves: the great Itaipu Dam.

A surprising number of travellers who come to Foz do Iguaçu skip the dam entirely, which I think is a massive shame. It is a marvel of modern engineering built jointly by the governments of Brazil and Paraguay, and seeing it up close is an unforgettable experience.

Getting there turned out to be incredibly easy and budget friendly. You can just head over to the main terminal bus station in town and hop on city bus 101 or 102, which drops you right at the visitor center. You can buy your entry tickets online ahead of time or right there at the counter.

When it comes to exploring, there are a couple of different tour options. The more detailed technical tour takes you deep inside the dam to see the massive generators and the inner workings of the facility. I opted for the Panoramic Tour, which is an open top double-decker bus ride that takes you all around the exterior and directly across the top of the dam itself.

Cruising across the top of the dam on the open air bus, I felt completely dwarfed by the whole thing. You look to one side and see this endless, quiet reservoir, and then you look to the other and there’s a massive, dizzying drop back down to the river. It really hits you in the gut that you’re just rolling along on top of a giant concrete wall that’s holding back millions of gallons of water. You can almost feel a low vibration humming through the structure, like the river is just fighting to push through the turbines. It’s one of those rare moments where you’re equally terrified by the sheer force of nature and totally mind blown by what humans can actually build.

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One of the coolest quirks of the ride? Since the dam literally bridges Brazil and Paraguay, the bus just casually rolls right over the border. For a few minutes, you’re suddenly in Paraguayan territory. No passports, no border guards, no stopping for immigration lines… just a quick, unofficial country hop on an open top bus. It was such a fun, wild little detail!

Mind-Blowing Facts (Courtesy of Our Awesome Guide):

Standing in front of this concrete behemoth is one thing, but understanding what it actually does is another. Our tour guide shared some incredible facts during the ride that really put the dam into perspective:

• A True Heavyweight: Until China built the Three Gorges Dam, Itaipu was the largest dam on the entire planet. However, even today, Itaipu still often produces more electricity annually than Three Gorges, thanks to the incredibly consistent water flow of the Paraná River.
• Powering Megacities: The energy generated here is staggering. The majority of the electricity produced on the Brazilian side is sent hundreds of miles away to power the massive metropolises of São Paulo and Rio de Janeiro. In fact, Itaipu supplies over 75% of Paraguay’s total electricity and around 15% of Brazil’s.
• The “Sounding Stone”: We learned that the name “Itaipu” translates to “the sounding stone” in the indigenous Guarani language, named after an island that existed near the construction site.
• A Modern Wonder: It is officially recognized as one of the Seven Wonders of the Modern World by the American Society of Civil Engineers. To give you an idea of its size, the guide noted that the amount of concrete used to build it was enough to build 210 Maracanã football stadiums!

If you ever find yourself in Foz do Iguaçu marveling at the waterfalls, do yourself a favor and set aside a half day for Itaipu. Feeling the sheer magnitude of the structure beneath your feet is a spectacular testament to what humanity can build, and a totally unexpected highlight of the region.