One thousand athletes from 26 states and Canada participated.
Now, there are 4 million athletes from 170 countries.
The first summer games were held on July 20 1968. Some of the first medalists are still competing.
Special Olympics started with track and field, swimming and field hockey. There are now 32 individual and team sports.
Athletes with intellectual disabilities between the age of 8 and 70 can compete.
"You have to place locally and then you advance on to the district levels and sectional levels depending on the sport state level and through the state you get nominated for different national events and world games," said Michael Benavente, Special Olympics administrator with the Chicago Park District.
"The most popular is obviously track and field many of the schools come out for track and field our partnership again with the Chicago Public Schools."
Amelia (56), Jim (52) and Pat (62) were among the first medalist. Pat still competes. Amelia and Jim "retired" from competing but are still active.
"Running walking and I do many things," Jim said.
Eleven-year-old Brian Martin is a young athlete who has won several medals. He plans to compete for many years.
"Softball and 50 meter run," Brian said.
"I don't have history going all the way back with them but to see them at the events and their smiles and just imagining what it was like in 1968 and to see that these guys are still out in the community and really still enjoying life is great," Michael said.
Special Olympics has been celebrating 45th anniversary with a week of events.
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