Twenty-nine stories. More than 300 feet straight up.
You may have noticed people climbing down the side of a building in downtown Denver this weekend. It's no superhero -- it's a fundraiser to fight cancer.
It's called "Over the Edge," a fundraiser made possible by the Cancer League of Colorado.
"I've got three days of people hopping off the side of a building," event co-chairman Jim Hackstaff told 7NEWS reporter Jason Gruenauer.
Each person who rappelled down the side of the 29-story Denver Energy Center building raised over a $1,000 to do so, all towards a fundraising goal of $250,000.
"All of the money raised, less the event expenses, goes to cancer research and it all stays in Colorado," Jackstaff added.
With spectators cheering on, Jennifer Bacon made her way down the 300-foot descent with her family on her mind.
"Eleven years ago my father died of testicular cancer and my stepfather has multiple myeloma that he's fighting, so this seemed like something important to support," she said.
Organizers said most rappellers have some connection to the disease. The money raised can be life-changing for those dealing with cancer, and the climb down can be life-changing for those who complete it.
"It's just something I always wanted to do. It's a challenge I didn't think I could do. And to be able to do that it's really exciting," Jennifer added.
About 180 people are expected to make the trip down over the course of the weekend.
7NEWS reporter Jason Gruenauer also took on the challenge, you can see part of his trip down by clicking on the video.