20-year-old woman dies after falling off Half Dome in Yosemite National Park

MARIPOSA COUNTY, Calif. -- A grieving father is opening up about the devastating moment his daughter fell from Half Dome in Yosemite National Park and did not survive.

"Knowing that she had great faith and that she was with her Lord was the only thing that kept me going. Knowing that I need to do things to make sure my life is in order so that I have a chance to see her again," said Jonathan Rohloff.

He shares how he managed to get through the heartbreaking moment his 20-year-old daughter, Grace Rohloff, slipped and fell off the mountain on July 13.

"Some of the last things she said is 'Dad, this was one of my bucket list items.' She was smiling from ear to ear, just so excited, she was so happy," said Rohloff.

Grace was a student at Arizona State with hopes of becoming a teacher.

By the age of 13, Grace had hiked the Grand Canyon.

She was not only an experienced hiker but was also athletic.

He explains they made it to the top of the mountain and enjoyed the view for roughly 20 minutes before dark clouds and rain rolled in.

It was on the way down when the unimaginable happened.

"Unfortunately, she lost control in between two of the wood slats and slid on the granite. It happened all quickly. I tried to reach down for her and reach out for her, and she went off the side, and it just happened in a heartbeat," said Rohloff.

Now, as Rohloff prepares to lay his daughter to rest, he's urging the National Park Service for change.

"They have a wooden slat that's about every 10 feet apart from each other. In between the 10 feet, the granite has been walked on so much, it's worn down, almost like a granite countertop. Once water gets on there, it just becomes very slick. There's no reason that they couldn't be a wooden plank every foot," said Rohloff.

Although he said it won't bring his daughter back, he wants to make sure future hikers are safe.

Rohloff says Grace was passionate about helping others.

He encourages people to donate to Grace's favorite charity in her honor.

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