A couple passes the sculpture “Transformer” by Chinese artist Bi Heng during snowfall in Kassel, central Germany, Tuesday March 12, 2013. Frankfurt airport closed, a quarter of flights out of Paris were canceled, Belgium suffered record traffic jams and high-speed trains were stuck in stations – all because of a sudden dump of oddly late snowfall on Western Europe. Less prepared for the kind of heavy snow that regularly hits northern and eastern neighbors, France, Britain and Belgium struggled Tuesday to keep moving amid the frosty, blustery conditions. (Photo by Uwe Zucchi/AP Photo/Dpa)

Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

Vlada Nikolchenko of Ukraine performs with the ribbon during the 36th European Rhythmic Gymnastics Championships in Kyiv, Ukraine, Sunday, November 29, 2020. Athletes from 23 countries participate in the championship in Kyiv. (Photo by Efrem Lukatsky/AP Photo)

Musicians in Father Frost costumes ride along Nevsky Avenue on the Dedmorobus (portmanteau of “Father Frost” and “bus”) musical bus to entertain citizens ahead of New Year celebrations in St Petersburg, Russia on December 28, 2020. (Photo by Alexander Demianchuk/TASS)

A man walks in the street at the start of the new curfew to counter the COVID-19 in the center of Lyon, central France, Saturday, January 16, 2021. All of France will be under a stricter curfew starting Saturday at 6 p.m. for at least 15 days to fight the spread of the coronavirus. (Photo by Laurent Cipriani/AP Photo)

People stand next to a ship, containing tonnes of hazardous mercury-mixed oil, as it was allowed to anchor at Gadani ship-breaking yard in Gadani, Pakistan, 28 May 2021. Authorities have launched an investigation into the anchoring of a ship at the Gadani shipbreaking yard despite Interpol's warning that the ship contains dangerous chemicals. (Photo by Rehan Khan/EPA/EFE)

A performer wearing a face shield looks on during a ceremony held by the Bangkok National Museum to celebrate the return of two ancient relics, believed to have been stolen from Thailand about 60 years ago, from the United States, in Bangkok, Thailand on May 31, 2021. (Photo by Soe Zeya Tun/Reuters)

A hiker admires the view as Mt. Etna, Europe's largest active volcano, erupts in the background, in the Bove Valley of Etna Park, on the eastern slope of Mt. Etna, in Sicily, southern Italy, Sunday, July 4, 2021. Since Feb. 16, 2021, Mt. Etna has begun a series of eruptive episodes. (Photo by Salvatore Allegra/AP Photo)