Romanian military doctors and medical students sit on a bus behind steamy windows before the National Day parade in Bucharest, Romania, Thursday, December 1, 2016. Military planes and helicopters flew over the Romanian capital Thursday as thousands turned out to celebrate the national day, marking the date when the country reunified with Transylvania in 1918. (Photo by Vadim Ghirda/AP Photo)

A pink elephant balloon, one of the entries in the Canadian Hot Air Balloon Championships, lands in a field in High River September 27, 2013. The event is a qualifier for the World Hot Air Balloon Championships in Sao Paulo in 2014. (Photo by Mike Sturk/Reuters)

A Raramuris indigenous woman takes part in the “Ultra maraton de los Canones 2017” (Ultra marathon of the Canyons), at La Sinforosa Canyon, in Guachochi, Chihuahua state, Mexico on July 15, 2017. More than 600 participants from different countries take part in the 63 and 100 kilometers races, along the Tarahumara mountain range. (Photo by Herika Martinez/AFP Photo)

Frida, a rescue dog belonging to the Mexican Navy, with her handler Israel Arauz Salinas, takes a break while participating in the effort to look for people trapped at the Rebsamen school in Mexico City, on September 22, 2017, three days after the devastating earthquake that hit central Mexico. (Photo by Omar Torres/AFP Photo)

The town hall with the Mangia tower is seen in Siena, central Italy, January 29, 2016. (Photo by Max Rossi/Reuters)

Police fire rubber bullets as they help an Atletico Paranaense fan during clashes between Vasco da Gama soccer fans and Atletico Paranaense fans at their Brazilian championship match in Joinville in Santa Catarina, on December 8, 2013. Dozens of fans fought a savage battle on the terraces at the match on Sunday, interrupting play for more than one hour and leaving at least three people reportedly in serious condition. (Photo by Carlos Moraes/Agência O DIA)

A visitor looks at a creation at the Artemide space during Milan Design Week, April 14, 2015. The Milan Design Week will be held until April 19. (Photo by Stefano Rellandini/Reuters)

“Window of Autumn” by Hasan Baglar taken in Nicosia, Cyprus, which has come first in the All About Plants Section for the RHS Photographic Competition 2019. (Photo by Hasan Baglar/RHS/PA Wire Press Association)