A masked reveller poses in San Marco Piazza during the Venice Carnival, January 30, 2016. (Photo by Alessandro Bianchi/Reuters)

A resident removes mud on a street brought by monsoon rains in San Mateo, Rizal, Philippines, August 14, 2016. (Photo by Erik De Castro/Reuters)

Carlos Melendez prepares to feed his pet squirrel “Colita” in downtown San Salvador January 29, 2015. (Photo by Jose Cabezas/Reuters)

A reveller takes part in the Gay Pride Parade in San Salvador, on June 24, 2017. (Photo by Marvin Recinos/AFP Photo)

Battle-weary American troops withdraw from Yong San in Korea. (Photo by Keystone/Getty Images). 1950

Jassen Todorov, 40, from San Francisco is a professor of music at San Francisco State University, but he took to helicoptering in his spare time. While he was content to keep the panoramic views he witnessed to himself, Todorov has now paired his passion for flying with photography to capture some of the United States’ undiscovered vistas. Here: Grand Prismatic Spring, Yellowstone, Wyoming. (Photo by Jassen Todorov/Caters News)

A man rides a horse through a bonfire as part of a ritual in honor of Saint Anthony the Abbot, the patron saint of domestic animals, in San Bartolome de Pinares, Spain, Saturday, January 16, 2016. On the eve of Saint Anthony's Day, dozens ride their horses through the narrow cobblestone streets of the small village of San Bartolome during the “Luminarias”, a tradition that dates back 500 years and is meant to purify the animals with the smoke of the bonfires and protect them for the year to come. (Photo by Francisco Seco/AP Photo)

A reveler takes part of the Light Festival parade in San Jose, Costa Rica on December 14, 2019. (Photo by Ezequiel Becerra/AFP Photo)