(CNN) -- The Olympic Games have grown dramatically since 1908 when they were first held in London.
Then just a little more than 2,000 athletes -- nearly all of them men -- competed for 110 gold medals.
But this summer, more than five times that many athletes, 10,500, are expected to compete for 302 gold medals.
All gold medals, however, are not alike.
The ones that will be awarded over the next two weeks contain just 6 grams of gold. They're mostly silver.
A century ago, the gold medals were entirely gold.
As the 2012 Games get under way, here are some other interesting facts and figures to consider:
Two -- The number of times London has hosted the Summer Olympics previously. They were in 1908 and 1948. London was scheduled to host the 1944 Summer Olympics, but they were canceled due to World War II.
37 -- The number of women who competed in the 1908 London Games
4,862 -- The number of women expected to compete in 2012, according to official Olympic data culled by The Guardian.
9 million -- The number of tickets sold for the 2012 Olympics.
80,000 -- The number of seats in London's Olympic Stadium.
$775 million -- Estimated cost of London's 2012 Olympic Stadium (£500 million). It is built from only a 10th of the total steel used to build Beijing's Bird's Nest stadium in 2008.
$15 billion -- Estimated amount of money spent by Great Britain to stage the entire Olympics.
2,300 -- The number of medals that will be handed out during the London Olympics.
1.34% -- The percentage of gold in an Olympic gold medal today.
1912 -- The last year that Olympic gold medals were 100% gold.
0 -- The number of gold medals awarded at the first modern Olympics in 1896. The winners actually received a silver medal instead.
27,974 -- The number of Olympic medalists from 1896 to 2010. This includes the Winter Olympics.
43 -- The number of events at the first modern Olympics in 1896. Fourteen countries participated in the competition in Athens, Greece.
302 -- The number of events at the 2012 London Olympics in 26 different sports.
Four -- The number of countries that have competed in every Summer Olympics since 1896. Those would be Greece, Australia, Great Britain and Switzerland.
18 -- The number of medals won by the most-decorated Olympic athlete, Russian gymnast Larysa Latynina. Latynina competed in the 1956, 1960 and 1964 Summer Olympics. Nine of her medals were gold, five were silver and four were bronze.
16 -- The number of Olympic medals won by the most-decorated American athlete, swimmer Michael Phelps. Phelps has won 14 gold medals, eight of which came in the 2008 Games.
Three -- The number of summer sports in which the United States has never won an Olympic medal. They are badminton, table tennis and handball.
13 -- The age of Marjorie Gestring when she won a gold medal in diving in 1936. The American is the youngest gold-medal winner in Olympic history.
62 -- The age of Sweden's Oscar Swahn when he won a gold medal in shooting in 1912. He is the oldest gold-medal winner in Olympic history.