This story originally appeared in the June 2014 edition of SPEED SPORT Magazine.

Long before the Unsers became the first family of the Indianapolis 500 they had established themselves as the “Kings of the Hill.” And this wasn’t any ordinary hill; it was the mightiest mountain of motorsports — Pikes Peak.

It was one of the first true tests of man versus machine versus nature when Spencer Penrose created the “Race to the Clouds” on the Pikes Peak Highway in 1916. The 92nd running of the Pikes Peak Int’l Hill Climb will be run June 29 on the 12.42-mile, 156-turn road that starts at 4,720 feet and climbs to the 14,110-foot summit.

Three-time Indianapolis 500 winner Bobby Unser has won 13 times in three classes at Pikes Peak, including eight wins in a 10-year period from 1956-’66. The driver that beat him in 1964 and 1965 was his younger brother, Al.

Uncle Louis Unser won Pikes Peak in 1946 and ’47. Other Unsers who have conquered Pikes Peak include Bobby’s son, Robby, and Bobby’s older brother, Jerry.

From 1946 through 1970, the event was part of the AAA and USAC Indy car national championship, so it was important for drivers such as the Unsers and Mario Andretti to perform well in the race up the mountain.

“It was my first big thing,” Unser said. “As a young kid it’s what I saw where my racing future might be. I didn’t know I was going to be there until later on. It was a national championship race and it was important to recognize that. It wasn’t a local barnyard special. All of the people in general from the Indianapolis 500 also went to Pikes Peak. It had a lot of credibility and the credibility is what excited the Unsers because the big names were there.

“And it was in the mountains. We were born and raised in the mountains.”

Bobby Unser was actually born in Colorado City, Colo., but his family moved to Albuquerque, N.M., when he was 1 year old. He was 7 the first time he went up Pikes Peak with his dad driving.

“It scared the crap out of me,” Unser recalled. “I was really a young kid but I remember it was awesome and scared the crap out of me, but it was the mountain.

“I don’t think there was any doubt that the Unser family was born into that event.”

When Bobby Unser first raced at Pikes Peak the cars were lacking technology and the road was all gravel.

“The Albuquerque Unsers looked at technology in a different way and we invented ways that were different than anything the Hill Climb had seen before,” Unser said. “We did it with handmade ways instead of money. We figured out ways to drive mountain roads and engineer cars to get more traction and tires that would work better at Pikes Peak that ended up being part of the history as far as engineering went.”

Some of those ideas were two-ply tires and utilizing walnut shells in the tires. By mixing walnut shells in the rubber when the car sped up the road the shells would fly out of the rubber and make the surface of the tire look like a sponge.

“That sponge would get a hold of that gravel and have three times as much grip as regular rubber would,” Unser recalled. “Nobody had thought of doing that before. It left behind a real coarse sponge and that got traction on that gravel like you wouldn’t believe. It all came about from testing and development.”

Unser was 22 when he made his first attempt up Pikes Peak in 1956. He knew the dangers involved, but didn’t consider it risky.

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