People walk under Australia's iconic landmark Harbour Bridge in Sydney on April 3, 2019, as heavy fog blankets the city. Low visibility due to heavy fog affected traffic in the city and caused flight delays at the Sydney airport. (Photo by Saeed Khan/AFP Photo)

In this March 14, 2015 photo, tourists take pictures from a viewing area at Iguazu Falls in Brazil. From walkways and bridges, viewers can count 270 water falls almost 100 meters (330 feet) high. (Photo by Jorge Saenz/AP Photo)

Pole dancers in Mexico have taken to the streets to celebrate their sport and show others the skills involved. The Pole Dance National Day celebration saw pole dancers gather in parks, outdoor gyms and on streets, using street lamps, sign posts and other objects to put on displays across Mexico City. Photo: A woman performs a pole dancing routine on a pedestrian bridge during the national day celebration of “Urban Pole” dance in Monterrey June 8, 2014. (Photo by Tomas Bravo/Reuters)

View of a damaged bridge at the Iguacu Falls on June 12, 2014, in Foz do Iguacu, Brazil, following the overflowing of the Parana river. In neighbouring Paraguay flooding has forced the evacuation of about 150,000 people in Paraguay's capital city Asuncion, authorities said. (Photo by Norberto Duarte/AFP Photo)

A member of the “Exit Point” amateur rope-jumping group jumps from a 44-metre high (144-ft) waterpipe bridge in the Siberian Taiga area outside Krasnoyarsk, November 3, 2013. Fans of rope-jumping, a kind of extreme sport involving a jump from a high point using an advanced leverage system combining mountaineering and rope safety equipment, marked the end of the group's jumping season and recent Halloween festivities. (Photo by Ilya Naymushin/Reuters)

A police officer stands at a police cordon near the scene of a terror attack in London, U.K., on Sunday, June 4, 2017. A van swerved into Saturday-night crowds on London Bridge, before three men got out and went on a stabbing rampage through nearby bars. (Photo by Luke MacGregor/Bloomberg)

Villagers use a makeshift bamboo bridge to move across flooded areas of Morigaon district in the northeastern Indian state of Assam August 20, 2014. The latest heavy rains have caused landslides and floods in many parts of India and Nepal, where at least 90 people have been killed since Thursday. (Photo by Reuters/Stringer)

In this photo taken October 16, 2012 and provided by Oracle Team USA, crew members of the capsized Oracle Team USA AC72 boat are rescued after being swept past the Golden Gate Bridge in San Francisco. The America's Cup champion syndicate is assessing the damage to its 72-foot catamaran, after it capsized and was swept by a strong current more than four miles past the Golden Gate Bridge before rescue boats could control it. (Photo by Guilain Grenier/Oracle Team USA/Associated Press)