Rays from the rising sun shine through the foliage of trees as fog covers the ground near the Guckler Karoly Observatory in Budapest, Hungary, 02 January 2017. (Photo by Balazs Mohai/EPA)
People with his face covered in oil and soot and carrying bull horns representing a devil join a carnival festival on February 14, 2015 in Luzon, Spain. (Photo by David Ramos/Getty Images)
A terrace of a house is covered with ash after the eruption of the Fuego volcano at San Miguel Los Lotes in Escuintla, Guatemala, June 6, 2018. (Photo by Carlos Jasso/Reuters)
Aerial view of a boat working in the green water of Taihu Lake covered by blue-green algae, Wuxi city, Jiangsu province, China on May 23, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)
Naked activists for animal rights, covered in fake blood, perform during a protest against the use of fur and leather, at Catalunya Square in Barcelona, Spain, December 16, 2018. (Photo by Albert Gea/Reuters)
A boy covers his head with fallen leaves as he enjoys a stroll with his family in a park in downtown Frankfurt, Germany, November 6, 2016. (Photo by Kai Pfaffenbach/Reuters)
Street musicians with their faces covered with animal masks play to earn some money in central Vienna, Austria, November 8, 2015. (Photo by Vasily Fedosenko/Reuters)
A couple watches the sunset over a sea of fog covering the Geneva Lake from Chardonne, Switzerland, 28 December 2015. (Photo by Jean-Christophe Bott/EPA)