CENTRE COUNTY, Pa. (WTAJ) — On a chilly Thursday morning, the “Old Men of the Mountains,” that’s what they call themselves, take a run on gravel roads to the top of Tussey Mountain in Boalsburg.

It’s about a 5 mile round trip. The only requirement is that you have to be 65 or older.

The leader of the group, George Etzweiler, has a birthday that makes him a numbers guy by default.

“March 14, 1920,” Etzweiler smiled. “The world calls it pie day because of 3.14.”

At 99, Etzweiler, a retired Penn State engineering professor, has been running for 50 years.

“I didn’t run a full mile one time in my life until I was 49,” he explained.

He’ll tell you his first real race was in November 1973. He was 53 with no intention of slowing down.

He’s well-known for being the oldest person to complete the historic, all uphill Mount Washington Road Race in New Hampshire. He has made it to the summit of the highest peak in the Northeast more than a dozen times.

“A run up Mount Washington is 7.6 miles with an average slope of 12 percent,” Etzweiler said. “The workout is about the equivalent to a 20K on Penn State’s campus.”

He’s not sure he’d call if love.

“Well, I guess that’s the word for it,” Etzweiler smiled.

It’s definitely not his one true love. His real romance, Mary, started before he even laced up his running shoes.

“She was my wife of almost 69 years,” Etzweiler said. “She died in December 2010 with pulmonary fibrosis. I suspect Mary’s support for me over the years helps to keep the motivation there.”

Mary is the one who supported him in every race.

“Whatever I’m doing I often think about her,” Etzweiler said. “She’s the inspiration for I think everything I’ve done.”

With Mary on his mind, just last month, George once again led the “Old Men of the Mountains” in the Tussey Mountainback 50 mile relay. The team completed the course in 10:29:39.

George makes sure he exercises every Tuesday, Thursday and Saturday.