A zookeeper feeds a hippopotamus with a watermelon in its enclosure in Belgrade's zoo, Serbia, July 20, 2015. Temperatures in Serbia have risen up to 40 degrees Celsius (104 degrees Fahrenheit), according to official meteorological data. (Photo by Marko Djurica/Reuters)

A hot air balloon competition called “Grudziadzkie Zawody Balonowe” is held in Lisie Katy, central-northern Poland, 14 May 2021. The compe​tition is held for the eighteenth time. (Photo by Tytus Zmijewski/EPA/EFE)

People are seen watching hot air balloons fly overhead during a two-day international hot air balloon festival in Eshkol Park near the southern city of Netivot, Israel July 22, 2016. (Photo by Amir Cohen/Reuters)

Hot-air balloons fly over Metropolitano park during the International Hot-Air Balloon Festival in Leon, state of Guanajuato, Mexico on November 19, 2023. (Photo by Henry Romero/Reuters)

This view shows giant hot air balloons of various shapes being lifted to begin flights from the Metropolitan Park over the city of Leon during the 2025 International Balloon Festival (FIG) in the state of Guanajuato, Mexico on November 15, 2025. (Photo by Mario Armas/AFP Photo)

Crews inflate hot air balloons during the 39th annual New Jersey Lottery Festival of Ballooning at Solberg Airport Friday, July 29, 2022, in Readington, N.J. The festival, which runs through Sunday, July 31, will feature as many as 100 balloons. (Photo by Julia Nikhinson/AP Photo)

Hot air balloons are displayed during an exhibition, in Caracas, Venezuela, 09 December 2022. The Government of Venezuela inaugurated an international transport exhibition to attract investment for a sector that has almost been paralyzed for the past five years but has begun to show signs of recovery this year. Venezuela has one of the most obsolete vehicle fleets in Latin America.. (Photo by Miguel Gutierrez/EPA/EFE)