Pro-government fighters stand next to a tank destroyed during recent fighting in Yemen's southwestern city of Taiz March 14, 2016. (Photo by Anees Mahyoub/Reuters)

Vocalist Laila Skovmand, a musician with Danish company Between Music, plays underwater in a tank during a rehearsal ahead of their UK premiere concert Aquasonic at the Tramway in Glasgow on Ocrober 25, 2017. (Photo by Robert Perry/PA Images)

A Ukrainian serviceman wearing a new year's hat waves at his comrades while standing beside his tank near Debaltseve, eastern Ukraine, February 8, 2015. (Photo by Gleb Garanich/Reuters)

Soviet Army soldiers sit on their tanks in front of the Czechoslovak Radio station building in central Prague during the first day of Soviet-led invasion to then Czechoslovakia on August 21, 1968. (Photo by Libor Hajsky/Reuters)

A woman looks at goldfish through the warped wall of a fish tank at the Art Aquarium exhibition in Tokyo July 10, 2015. Several thousand goldfish are displayed in dozens of uniquely shaped tanks, using LED lights, projection mapping and music in a show that was produced by Japanese designer Hidetomo Kimura. (Photo by Thomas Peter/Reuters)

A pro-democracy demonstrator fights with a Soviet soldier on top of a tank parked in front of the Russian Federation building on August 19, 1991, after a coup toppled Soviet President Mikhail Gorbachev. The same day, thousands in Moscow, Leningrad, and other cities answered Russian Republic President Boris Yeltsin's call to raise barricades against tanks and troops. (Dima Tanin/AFP/Getty Images)

Myanmar T-72 battle tank competes in an individual race of the Tank Biathlon competition as part of the 7th International Army Games 2021 at the Alabino training ground, Moscow region, Russia, 27 August 2021. The 7th International Military-Technical Forum “Army-2021” is held from 22 August till 04 September 2021 at 23 military training grounds of 11 countries. Five thousand participants of 277 teams from 42 countries compete in 34 military contests. (Photo by Sergei Ilnitsky/EPA/EFE)

Iguazu Falls are waterfalls of the Iguazu River on the border of the Brazilian state of Paraná and the Argentinian province of Misiones. The falls divide the river into the upper and lower Iguazu. The Iguazu River rises near the city of Curitiba. It flows through Brazil for most of its course. Below its confluence with the San Antonio River, the Iguazu River forms the boundary between Argentina and Brazil.