Željava Air Base, situated on the border between Croatia and Bosnia and Herzegovina under Plješevica Mountain, near the city of Bihać, Bosnia, was the largest underground airport and military air base in the former Yugoslavia, and one of the largest in Europe. (Photo by Thomas Windisch/Exclusivepix Media)

General view of Chilean Calbuco volcano from Puerto Montt, located at 1000 km southern Santiago de Chile, Chile, 22 April 2015. Due to the eruption of the volcano with a smoke column 20 km high, authorities declared a red alert and ordered the evacuation of around 1500 inhabitants of Ensenada, Alerce, Colonia Río Sur and Correntoso towns. (Photo by Alex Vidal Brecas/EPA)

In this July 23, 2013 photo, sand fills an abandoned house in Kolmanskop, Namibia. Kolmanskop, was a diamond mining town south of Namibia, build in 1908 and deserted in 1956. SInce then, the desert slowly reclaims its territory, with sand invading the buildings where 350 German colonists and more than 800 local workers lived during its hay-days of the 1920s. (Photo by Jerome Delay/AP Photo)

A “creuseur”, or digger, a plastic lantern on his head, readies to enter a copper and cobalt mine in Kawama, Democratic Republic of Congo on June 8, 2016. Cobalt is used in the batteries for electric cars and mobile phones. Working conditions are dangerous, often with no safety equipment or structural support for the tunnels. The diggers say they are paid on average US$2-3/day. (Photo by Michael Robinson Chavez/The Washington Post)

Police officers introduce a litter of golden retriever puppies to be trained as police dogs during a ceremony at the National Police Academy in La Paz, Bolivia, Monday, August 16, 2021, the date of the feast day for Saint Roch, considered the patron saint of dogs, among other things. (Photo by Juan Karita/AP Photo)

A destroyed tank sits by the side of a road leading to Abi Adi, in the Tigray region of northern Ethiopia, on Tuesday, May 11, 2021. The Tigray People’s Liberation Front was on top of a coalition that ruled Ethiopia for nearly three decades. That changed in 2018, when Prime Minister Abiy Ahmed rose to power as a reformist. Abiy alienated the TPLF with efforts to make peace with its archenemy, Eritrea, and rid the federal government of corruption. (Photo by Ben Curtis/AP Photo)

Pfc. Esmeralda Calderon stands and salutes the flag on the 15th green during the first round of the LPGA golf tournament at Kingsmill Resort and Golf Course in Williamsburg, Va., Thursday May 23, 2019. Pfc. Calderon, from San Antonio, Texas, is a Marine assigned to Naval Weapons Station Yorktown. (Photo by John Sudbrink/The Daily Press via AP Photo)

Tigray refugees who fled the conflict in the Ethiopia's Tigray ride a bus going to the Village 8 temporary shelter, near the Sudan-Ethiopia border, in Hamdayet, eastern Sudan, Tuesday, December 1, 2020. (Photo by Nariman El-Mofty/AP Photo)