I'm wondering if there's a deeper divot in the earth beneath Walt Disney World Resort right now. Fifty-thousand runners -- and about as many spectators -- are taking part in Walt Disney World's Marathon weekend.

Forgot to sign up? Well, you can't, I'm afraid. All four races are sold out, and they went fast.

But runners taking the all-new Dopey Challenge may want to opt for the slow-n-steady approach instead. That's because, for the first time ever, the uber-popular annual event has a 5K, 10K, half-marathon and full-marathon in the span of 4 days.

That's 48.6 miles, folks. Seven-thousand people are taking the Challenge.

"I don't know what I'm thinking!" William Jensen from Baltimore told me. This is actually his first marathon - ever - and he's about to run for 4 days.

"It's all about the medals," Chuck Weyant of Flagler Beach was quick to say when asked why he's putting his body through this. "You get six medals."

Hm, I wonder if he'll sell them on ebay?

"No! You kidding me?" he said, shocked. "Are you kidding me? It ain't happening."

John Moulind says he flew 28 hours from Sydney, Australia to race.

"Four races in 4 days - I don't know what to expect," he said. But it was obvious that he was getting stoked. "Have a look around! The atmosphere, the vibe, good people, fun place. Most magical place on earth."

So how on earth do you get your body in optimum race condition?

"Sleep a lot," said 15-year-old Pete Moulind, also visiting from Australia.

"I am going to be eating a lot and sleeping a lot," laughed Dawn Snowball of Casselberry, who is attending her 3rd straight Walt Disney World Marathon Weekend.

But for Amy Newman of Tampa, running through all 4 Disney parks means there's a bunch of very cool stuff to look at.

"There's characters along the way also," she said, "so you can pull off from the race and go get your autograph."

Disney says 25,000 people are running the half marathon and 26,000 are running the full.

"We are the largest endurance weekend in the United States right now," said Disney Sports Marketing Director, Faron Kelley. "There's nothing bigger. And we think we might be the biggest event that happens in Central Florida."

Just curious -- how do you reward yourself for crossing the finish line?

Jensen laughed big time. "I think a lot of drinking!"