The Olympic Games in Rio de Janeiro are finally here. For the next two weeks, sports fans around the world will be glued to the games to watch about 11,000 athletes compete for gold medals and glory. But how much do you know about the event itself?

The Olympics are an ancient tradition dating back to 776 BC. Originally intended as a way to honor Zeus, the first modern iteration took place in Athens in 1896 with 241 male athletes from 14 countries, according to

For a while, there were only Summer Olympics — the Winter Games didn't begin in 1924. Then, for decades, both the summer and winter Olympics were held every four years — in the same year. That changed in 1986, when the International Olympic Committee chose to split them up in an effort to "concentrate greater attention on the Winter Games, which, until now, had been widely regarded as a less-important preliminary to the Summer Games," the Los Angeles Times wrote.

Here are 16 other facts about the history of the summer Olympics, mostly collected from History on the Net, the History Channel, Tufts University and the World Atlas:

The first Olympics only had one event: a race.

The games were banned in 394 AD because they were linked to paganism.

Women were allowed to compete starting in 1900.

The Olympics used to have a special truce that allowed athletes and spectators to travel through various countries without fear of persecution. 

The Summer Olympics have been held in England, the United States, Greece, Finland, Germany, Mexico, France, Sweden and China, among other countries.

The first time a camera was used to determine who won a race — called a photo finish — was in 1912.

The U.S. has the most medals earned at Summer Olympic Games, followed by Russia and Germany.

Bangladesh has never won a medal.

Germany and Japan weren't invited to the 1948 games because of their involvement in World War II.

Gold medals were actually pure gold through 1912.

This year, they're 494 grams silver and 6 grams gold, according to CNN.

If you melted and sold them, they'd be worth about $600 apiece.

The last time golf was an Olympic sport was in 1904.

The Olympics were canceled in 1916, 1940 and 1944 due to war. 

The Rio Olympics are the first time the games have been in South America. 

The 2020 Summer Games will be in Tokyo.