Every Summer Olympics fans get a chance to watch a whole array of sports they only watch every four years.
Whether it's speed climbing, artistic swimming, or the steeplechase for two weeks many of us become instant experts on unusual, complicated sports that we'd never heard of three days earlier.
Perhaps the most unusual of those sports in the modern pentathlon.
First introduced to the modern Olympics in 1912, the event has its origins in the pentathlon of the ancient Olympic Games.
While both events have five disciplines, that's where the similarities end. In the ancient pentathlon competitors entered a running race, followed by a javelin throw, discus throw, and long jump, before finally competing in a wrestling match.
By contrast, the modern pentathlon - introduced to the games in 1912 by Baron Pierre de Coubertin, the founder of the modern Olympic Games - tests the skills required by soldiers in the 19th century.
According to a 19th-century story, the events in the modern pentathlon are based on a young French cavalry officer who was sent on horseback to deliver a message.
While on his journey, he had to ride a horse, fight with a sword, shoot, swim and run. Those five disciplines make up the sport as we know it in 2021.
Uniquely, all events are conducted on the same day as to truly mimic a day of a soldier.
Throughout the events, athletes accumulate points and this gives them an advantage in the final race which decides who wins gold.
De Coubertin, according to the Olympics, said that sport should test "a man's moral qualities as much as his physical resources and skills, producing thereby the ideal, complete athlete."
The modern pentathlon does just that.