Military helicopters fly in formation above a billboard with a picture of China's late Chairman Mao Zedong during a training session for the upcoming parade marking the 70th anniversary of the end of World War Two, on the outskirts of Beijing, July 2, 2015. Troops from Russia and Mongolia will march together with Chinese forces in a parade in Beijing in September to commemorate the end of World War Two, the government and state media said on Thursday, confirming the first two foreign participants. (Photo by Jason Lee/Reuters)

These otherworldly images give a rare glimpse inside caves barely ever seen by the human eye. With its peculiar pools of water and strange colored sediments, the bizarre looking tunnels of the Shakuranskaya cave could be a set straight out of a science fiction film. Found in the disputed region of Abkhazia, around 75 miles outside of Sochi, Russia, it is rumored the incredible underground chambers were formed after a huge earthquake struck the area in 1892. After causing part of a nearby mountain to collapse into the Amtkel River, it is thought the dam-like affect has created a series of interconnecting underground tunnels. Here: a large pool of water inside one of the tunnels. (Photo by Vladimir Mulde/Caters News)

History enthusiasts of French association “Arquebusiers de l'Est”, dressed as soldiers of 3rd regiment of Zouave, attend an Armistice Day ceremony to commemorate the end of World War One at Epernay, eastern France, November 11, 2014. More than a hundred volunteers from France, Romania, England, Belgium, Russia and Italy took part in the parade. The year 2014 marks the centennial commemoration for the soldiers who fought in the First World War (WWI). (Photo by Charles Platiau/Reuters)

A model wears a creation for Schiaparelli's Haute Couture Fall/Winter 2022-2023 fashion collection, Monday, July 4, 2022 in Paris. (Photo by Lewis Joly/AP Photo)

Revelers during the Leeds Festival 2022 at Bramham Park in Leeds, United Kingdom on August 26, 2022. (Photo by Danny Lawson/PA Wire Press Association)

“Igor Sikorsky (May 25, 1889 – October 26, 1972), born Igor Ivanovich Sikorsky was a Russian American pioneer of aviation in both helicopters and fixed-wing aircraft. He designed and flew the world's first multi-engine fixed-wing aircraft, the Russky Vityaz in 1913, and the first airliner, Ilya Muromets, in 1914. After immigrating to the United States in 1919, Sikorsky founded the Sikorsky Aircraft Corporation in 1923, and developed the first of Pan American Airways' ocean-conquering flying boats in the 1930s. In 1939 Sikorsky designed and flew the Vought-Sikorsky VS-300, the first viable American helicopter, which pioneered the rotor configuration used by most helicopters today. Sikorsky would modify the design into the Sikorsky R-4, which became the world's first mass-produced helicopter in 1942”. – Wikipedia

Photo: Westland Sikorsky H-5's, used by British European Airways Helicopters, which fly between London and Birmingham. The Sikorsky H-5, (aka R-5, S-51, HO3S-1, or Horse) (R-5 until 1948; company designation VS-327) is a helicopter built by Sikorsky Aircraft Corporation, formerly used by the United States Air Force, and its predecessor, the United States Army Air Forces, as well as the United States Navy and United States Coast Guard (with the designations HO2S and HO3S). (Photo by Harrison /Topical Press Agency/Getty Images). 22nd May 1951

Richard Winsor, Ashley Shaw, Zizi Strallen, Glenn Graham, Nicole Kabera, Harrison Dowzell, Will Bozier and Cordelia Braithwaite during a photo call for Sir Matthew Bourne's The Car Man at the Royal Albert Hall, London on May 11, 2022, a reinterpretation of Bizet's Carmen, staged in 1960s American diner-garages with a specially expanded 65-dancer production for the hall, as part of its 150th anniversary. (Photo by Ian West/PA Images via Getty Images)

Pupils Antonio Marin-Kalisz, 10 (left) and Zofia Krolikwska, 11 (right) from St Mary's Primary School in Leith, UK with local celebrity chef Tony Singh at the unveiling of Edinburgh Community Food's new educational tuk-tuk on Wednesday, October 2, 2024. The tuk-tuk will serve as a mobile educational initiative to teach communities about nutrition by making healthy cooking fun and accessible, and taking it into the heart of the community. (Photo by Jane Barlow/PA Images via Getty Images)