The Vietnam Slide Project was created by photo editor Kendra Rennick, who began collecting photo slides after a close friend lost her father, a Vietnam veteran. Her friend found a box of slides that her father had taken while in Vietnam and from there Rennick has continued to collect photographs that Vietnam veterans took during their tours of duty. Here: A photo taken from the collection of D.Thornton, who served in the First Air Cavalry division of the United States Army. (Photo by D.Thornton/The Vietnam Slide Project)

Stanislav Fursov (top) and Ekaterina Simonova from Russia, who are representing the city of Moscow, dance during the Stage style final round at the Tango World Championship in Buenos Aires, Argentina, August 27, 2015. (Photo by Marcos Brindicci/Reuters)

Italian Air Force's aerobatic demonstration team, the Frecce Tricolori leave colourful vapour trails as they fly over the Altare della Patria monument on Republic Day (Festa della Repubblica) in Rome, Italy, 02 Jun 2017. The anniversary marks the founding of the Italian Republic in 1946. (Photo by Massimo Percossi/EPA)

A festival goer spins a light strip as she dances to electronic music in front of the Belleville stage during the 45th edition of the Paleo Festival, in Nyon, Switzerland, 24 July 2022. The Paleo is the largest open-air music festival in the western part of Switzerland. (Photo by Valentin Flauraud/EPA/EFE)

Picture dated October 8th, 2022 shows Patrouille Suisse, the official Swiss Air Force jet aerobatic display team flying at Duxford Flying Finale in Cambridgeshire, the final airshow of the season. (Photo by Caroline Haycock/Bav Media)

Tourists view Hukou Waterfall on the Yellow River in the frigid winter on December 28, 2023 in Yan'an, Shaanxi Province of China. Freezing winter air has turned Hukou Waterfall into an icy wonderland. (Photo by VCG/VCG via Getty Images)

Keeper Silvia Salvatierra, 59, is kissed by a chimp named “Jony”, 54, who was rescued from a circus, at the Lujan Zoo from where felines, including tigers and lions, will be transferred to a wildlife sanctuary in India, in Lujan, on the outskirts of Buenos Aires, Argentina on April 8, 2024. (Photo by Agustin Marcarian/Reuters)

Team Kazakhstan throw Zhaklin Yakimova of Kazakhstan into the air while they perform their routine in the Mixed Team Acrobatic during the World Aquatics Artistic Swimming World Cup 2024 - Stop 2 at Aquatics Centre on May 05, 2024 in Paris, France. (Photo by Adam Pretty/Getty Images)