Last week, United World Wrestling's Executive Committee approved existing plans to host the 2020 Senior Wrestling World Championships December 12-20 in Belgrade, Serbia. 

United World Wrestling's Instagram provided a look back at some of the most significant freestyle "Moments in History" at the World Championships.

In 1951, Turkey claimed six of the eight freestyle gold medals at the World Championships.

In 1961, Iran became the first Asian team to win freestyle title, accomplishing the feat in Yokohama, Japan.

In 1967, Ali ALIEV (URS) became the first five-time freestyle world champion. His gold medals came in 1959, 1961, 1962, 1966 and 1967. That same year, the Soviet Union captured its 19 straight freestyle world team title. 

In 1970, Abdollah MOVAHED (IRI) capped off a five-year undefeated world championship run (1965-1970) and became the first Asian wrestler to win five world golds in freestyle. 

In 1971, Alexsandr MEDVED (URS) claimed his historic seventh world title. His world titles came in 1962, 1963, 1966, 1967, 69, 70 and 71)

In 1975, Zevegiin OIDOV (MGL) became the first and only Mongolian ever to win back-to-back world titles.

In 1985, Raul FONSECA (CUB) became Cuba's first-ever freestyle world champion after defeating Dave SCHULTZ (USA) in the gold-medal match.

In 1987, Sergei BELOGLAZOV (RUS) won his sixth world title. "Even if you win the world championships, that next day you need to start over," said Beloglazov. "You're nobody and need to start fresh."

In 1992, John SMITH (USA) completed his run of four straight world titles. "I earned the right to be able to hit sharp techniques," said Smith. "It had nothing to do with talent. It had to do with a commitment to getting better."

In 1993, the United States won the freestyle world team title in Toronto, Canada, to become the first Pan American team to win freestyle world team title. 

In 1995, Valentine YORDANOV (BUL) made history by becoming the first freestyle wrestler to win 10 world medals (7 golds, 2 silvers and 1 bronze).

In 1999, Daniel IGALI (CAN) defeated Lincoln MCILRAVY (USA) to win Canada's first world title in freestyle wrestling. 

In 2003, Arif ABDULLAEV (AZE) topped Quintana MIGUEL (CUB) in the world finals to become Azerbaijan's first-ever world champion in any style. 

In 2005, freestyle wrestling great Buvaisar SAITIEV (RUS) won his sixth and final world title. 

In 2010, Sushil KUMAR (IND) became the first-ever Indian wrestler to win a world title. "2010 was the best year," said Kumar. "Wherever I went, I won gold. Commonwealth Games, Asian Championships, World Championships."

In 2011, Jordan BURROUGHS (USA) captured his first of four world titles in his world championship debut in Istanbul, Turkey. 

In 2018, Takuto OTOGURO (JPN) became Japan's youngest-ever freestyle world champion at the age of 19.