Morton the Sea Monster, better known as the Nantucket Sea Monster, is one of the classic novelty balloons in the Macy's Thanksgiving Day Parade.
History with the Macy's Parade.
The balloon was created for a publicity stunt in Nantucket, Massachusetts back in 1937. It was first claimed to have been seen by a local fisherman in August of that year. This was initially dismissed as a lie, but when a second resident also claimed to have seen it, rumors began to spring up. When it's 66" by 45" footprints popped up on the beach, the town was convinced there really was something out there. About a week later, the townspeople were surprised to see the beast beached on the shore. It was a monster--a monster shaped rubber balloon, that is.
The truth came out; local puppeteer Tony Sarg had created the 125-foot critter to stir up business for his store, which was starting to lose sales. While the business didn't profit from the stunt, the town did; people all across the country began to flock to the colossal creature. Eventually, Morton became so popular he appeared in the Macy's parade.
He reappeared in the 1937 Parade, But his color changed from green to red.
Of note, Morton is generally said to be the longest balloon ever seen in the parade with 125 feet in length. While longer balloons have been reported, Morton is the longest that can be verified.