The road to the top of Mount Diablo might be crowded this Sunday.
Nearly 800 cyclists will be riding up the mountain on that day, competing in the 31st annual Mount Diablo Challenge. The deadline to register is noon Thursday.
The event is organized by Save Mount Diablo as part of their campaign to publicize the amenities of the mountain.
The summit road will be closed to cars during the race.
Cyclists will set out at 8:30 a.m. from The Athenian School in Danville. They'll ride 11.2 miles to the mountain summit. The record, set in 2009, is 41 minutes, 25 seconds.
Among the crowd will be Michael Royse, a 38-year-old mailman from Antioch who was diagnosed with type 1.5 diabetes two years ago.
When he was younger, Royse rode in two of the Mount Diablo Challenge events. After his diabetes diagnosis, he started cycling again.
He rode in last year's challenge, climbing the mountain in 1 hour, 22 minutes. He's back this year to see if he can hit his goal of 1 hour, 15 minutes.
"I was looking for a challenge and it (Mount Diablo) was there. It's a pretty big one," said Royse.
The married father of a 7-year-old son, Royse cycles several times a week, including an occasional trip up Mount Diablo.
He says he has lost weight the past couple years and the cycling has helped improve his health.
"I feel great. My doctor says I'm a boring patient," Royse said.
Royse says cycling, especially up the mountain, is also a great stress reliever.
"Anything that is bothering me is peeled away when I'm cycling," he said. "I come down from the mountain with a fresh new perspective."