They come from all over the state and wait in line for hours.
"It's become sort of a yearly event for us. We've been doing it for eight or nine years now -- we're having a blast," said Ed Sayers of Corinth.
It's the 20th annual Chelsea Road Rally. Drivers decipher a series of clues dreamt up by Chelsea native Will Gilman, that take them for drive through Orange County's back roads for hours.
"Once people try it, they really get hooked. It's sort of like a detective story and so once you really get into it, it's really tough to give up on," Gilman said.
Gilman's game has become a mainstay in the town over the years. He was involved in a motorcycle accident in 1976 that left him paralyzed, and those who know him say his injuries have never slowed him down.
"Will is one amazing person who would never want recognition, but certainly deserves it," said Gilman's friend, Gail Isham.
"You only have one life to live, so you do it anyway," Gilman said.
And he does -- Gilman spends 20 to 30 hours on the road, creating the clues that start out as simple plays on words. "So there may be a red door in the barn way back to your left and it says 'Put the red door in your rear view,'" he said.
But the clues grow more difficult as the day goes on. Beginners often get lost and give up, but many say they come back the next year better prepared.
"We have our dictionary, we have the volume library, we have an atlas," said Penny Carpenter, a rally participant.
"I have to outsmart them somehow. They need to make a mistake. If I had 10 cars without making a mistake, how do you decide who wins?" Gilman said.
Every car gets a number -- and nickname. "We got out name because we'll end up going the wrong way and we'll say -- 'oops,'" said Anthony Brock.
And each participant pays $7 for fun that -- for some who get lost -- can last at least five hours.
The funds raised go toward a local baseball organization and pay for dinner for everyone.
"We have quite a cook out at the end. They get their money's worth just in hamburgers, hot dogs and baked beans and salads and all," Gilman said.
2013 was a record setting year -- 70 teams participated in the 20th annual rally -- which Gilman says is the biggest turnout yet.