There have certainly been some "sports" which, thankfully, are no longer in the Olympics. Having said that, the Swimmig Obstacle Race would have been worth watching.
1900 - Hot Air Ballooning
The 1900 Olympic Games were held during the Great Exposition in Paris. There were hot air balloon races on the outskirts of the city in Vincennes. Athletes were judged on distance traveled, time in the air and ability to land at the right coordinates. It was only removed from the Olympics because there was a ban on motorized sports.
1900 - Swimming Obstacle Race
Mix water and obstacles and you have this sport. It was only held once at the Olympic Games in Paris and it was crazy! Swimmers had to complete a 200-metre swim in the River Seine while climbing over a pole, scrambling over and then swimming under rows of boats. Amazingly the winner completed the race in 38 seconds.
1904 Distance Plunging
ST. LOUIS, U.S. — Only one country competed in this weird event at the 1904 Olympic Games in St. Louis, which is no surprise. It involved diving into the water and then going as far as possible underwater without moving any body parts. The winner was whoever coasted the longest distance in 60 seconds, or when they floated to the surface, whichever came first.
1984 Solo Synchronized Swimming
LOS ANGELES, U.S. — Sounds a little weird when you think about it, but when this sport made its debut at the Los Angeles 1984 Olympic Games, they tried to claim that the swimmers were synchronizing with the music. So there was one poor swimmer, dancing to her own beat in the water. No wonder it didn't last.