Presenter Gaby Roslin said she was left "jellified" by a 100ft head-first charity abseil.
The 46-year-old decided to take the plunge in the style of Tom Cruise in Mission Impossible to help raise funds for children's cancer charity CLIC Sargent, of which she is a patron.
Roslin was joined by 170 other people for the abseil, the first to take place inside The O2 arena in London.
Speaking moments after the 30-second freefall, the television and radio personality said: "I wasn't going to come down face first, but I thought I would regret it if I didn't.
"It wasn't like abseiling how I did it 20 years ago on children's TV. When you're walking onto wobbly steel girders on top of The O2, every part of your body is telling you not to do it.
"I asked if I could change my mind, but they said no. But when you let go and start moving, it's fantastic. I loved it."
It is hoped £30,000 will be raised by the day's abseiling, in which participants also had the opportunity to descend the rope in a more traditional manner.
Roslin said she would do the abseil again if she could - and added that she was looking forward to boasting to celebrity friends Paul Ross and Alan Carr that she had completed the challenge.
She was cheered on by her children at the arena and declared herself to be "exhilarated" after landing on solid ground.
She said: "It was when I was walking out that my legs turned to jelly, my arms turned to jelly. I thought I was going to cry with fear. I was jellified. But sometimes in life you have to face your fears."