Since 1927, the balloons were grounded only once, in 1971. The wind was too powerful that day. And the parade itself was canceled only three times, from 1942 to 1944. That's because of rubber and helium shortages during World War II. Macy's helped the war effort by giving 650 pounds (about 295 kilograms) of balloon rubber to the government.

One year, a tug-of-war broke out after a balloon landed. People yanked it until they tore it apart. Another year, a loose balloon got tangled up in the propeller of a small plane. The balloon almost took it down. That ended that tradition! (Now, the balloons are deflated and crated. Then they're stored for the next year.)

About 3.5 million people show up annually to see the Macy's Thanksgiving Day Parade. There's a 2.5 mile (about 4 kilometer) route. And another 50 million people watch it on TV. It's one of the most-viewed broadcasts year after year. The parade is more than just a big balloon blow up and blowout. It's an American institution.

The 1924 parade featured floats with Mother Goose characters. There were Macy's employees dressed as clowns and cowboys. There were even four marching bands! There were bears and elephants from nearby Central Park Zoo. But there were no giant balloons. Those made their debut in 1927 as a replacement for the zoo animals. The roars and growls scared kids.

Some animals from the Central Park Zoo took part in the first Macy's Thanksgiving Day Parade.

The popular Macy's Thanksgiving Day Parade has only been canceled three times.

Some early balloons were made to slowly leak helium so that they would drop back to earth.

The parade is a popular tradition with many things to see, but the balloons are the main event.