The Rio de Janeiro Olympics kick off on August 5 for some two weeks of competitive games drawing athletes as well as audiences from around the world. As they prepare to cover the event, Reuters photographers look back on their favourite pictures from past Olympics where they captured the action on the ground as well as the participants' tears and joy that followed. (Photo by Lucy Nicholson/Reuters)

This photo provided by Steamboat Ski Resort shows hot air balloons that visitors can tour in above the town and mountains in Steamboat Springs, Colo. Wild West Adventures offer continental breakfast, champagne ceremony with flight certificates and courtesy pick-up are included. (Photo by Larry Pierce/AP Photo/Steamboat Ski Resort)

The November 2018 Square Print Sale, presented by Magnum Photos and Aperture, brings together over 100 images to explore perspectives on transition and transformation in photography. Here: New York City, 1965, by Joel Meyerowitz. “A girl on a Vespa on her way to who knows where, when the light stopped her at the 72nd street crossing near the Dakota, where John Lennon would one day cross paths with his fate. She takes this moment to finesse a fingernail before she resumes her downtown journey, while I, stopping at the same crossing, but on foot, leap into the street to capture this vision of a dream girl before time takes her on her way”. (Photo by Joel Meyerowitz/Courtesy Aperture)

A person enter in sauna on the peak of Mount Lagazuoi in Cortina D'Ampezzo, Italy January 16, 2018. Picture taken January 16, 2017. (Photo by Stefano Rellandini/Reuters)

A demonstrator catches fire during clashes with riot police within a protest against Venezuelan President Nicolas Maduro, in Caracas on May 3, 2017. Venezuela's angry opposition rallied Wednesday vowing huge street protests against President Nicolas Maduro's plan to rewrite the constitution and accusing him of dodging elections to cling to power despite deadly unrest. (Photo by Ronaldo Schemidt/AFP Photo)

A cosplayer poses during Day 2 of London MCM Comic Con 2019 at ExCel on May 25, 2019 in London, England. (Photo by Jack Dredd/Rex Features/Shutterstock)

A man carries a sheep after it was rescued from mud in Sanliurfa, Turkey on January 9, 2019. Total of 67 sheep and a donkey rescued from mud by gendarmerie forces, firefighters and local people in Sanliurfa's Bozova district. (Photo by Halil Fidan/Anadolu Agency/Getty Images)

A cleaning staff waers protective gear to disinfect a metro carriage as a prevemtive measure against the spreading of the COVID-19 coronavirus in Addis Ababa, Ethiopia, on March 20, 2020. African countries have been among the last to be hit by the global COVID-19 coronavirus epidemic but as cases rise, many nations are now taking strict measures to block the deadly illness. (Photo by Michael Tewelde/AFP Photo)