Guests arrive for the Arlo Guthrie concert at the Bethel Woods Center for the Arts, the original site of the Woodstock Festival, on the 50th anniversary in Bethel, New York, U.S. August 15, 2019. (Photo by Brendan McDermid/Reuters)

At the 50th anniversary of the Hartford Automobile Club a 1914 Mercer with an economical wind screen, looking like a large magnifying glass, designed to offer minimum wind resistance. Brass is used instead of chrome for the “shiny” parts, circa 1955. (Photo by Three Lions)

The dancers are posing after the Topeng Bekasi dance performance, a presentation from the West Java Pavilion, during the 50th anniversary celebration of Taman Mini Indonesia Indah (TMII), in Jakarta, on Sunday, April 20, 2025. (Photo by Andri Munazir/ZUMA Press Wire/Alamy Live News)

Filipa Martins of Portugal fails to grab the bar as she performs the uneven bars during the Women's All-Around Final at the 50th FIG Artis​tic Gymnastics World Championships in​ Kitakyushu, Japan, 21 October 2021. (Photo by Kimimasa Mayama/EPA/EFE)

Seth Moniz and Kelly Slater, of the United States, embrace after Slater won the Billabong Pro Pipeline contest just short of his 50th birthday in Haleiwa, Hawaii, US on February 5, 2022. (Photo by Brent Bielmann/World Surf League via AP Photo)

Fireworks explode above Singapore's financial skyline at dusk as part of celebrations for the nation's 50th year of independence, Sunday, August 9, 2015, in Singapore. Singapore declared independence on August 9, 1965. (Photo by Wong Maye-E/AP Photo)

Swedish climate change activist Greta Thunberg, Isabelle Axelsson and German Luisa Neubauer take part in a climate strike protest during the 50th World Economic Forum (WEF) annual meeting in Davos, Switzerland on January 24, 2020. (Photo by Denis Balibouse/Reuters)

Jaime “Ka Diego” Padilla (R), spokesperson of the Melito Glor Command of the New People's Army (NPA), and Ka Kathryn (Comrade Kathryn) (L) react during their 50th founding anniversary celebration at an undisclosed location in the mountains of Sierra Madre, Philippines, 31 March 2019. (Photo by Alecs Ongcal/EPA/EFE)