While friends and family were saddened by Mark Harrington's sudden death from a heart attack, they say they were comforted by the fact that he died doing one of the things he loved: mountain biking.

Known and liked by many in local mountain biking circles, Harrington was with his son in Annadel State Park, one of his favorite biking spots, when he had a fatal heart attack on Dec. 28. He was 63.

Harrington had long enjoyed mountain biking but became particularly active several years ago, joining the Annadel Mountain Biking Group in 2011, said his daughter, Vaneza Harrington. He went mountain biking almost every weekend.

"We were pretty fortunate to have him," said Sebastian Brewer, a co-organizer of the Annadel Mountain Biking Group, which he helped to create on Craigslist in 2010 and has grown to about 700 members.

Brewer got to know Harrington in September 2011, when the two drove together to a mountain biking excursion near Garberville. Harrington, an intermediate to advanced rider, took it upon himself to attend many beginner rides and help out fledgling bikers.

"He loved to see new riders," Brewer said. "He was like a liaison to the new guys. He loved to help people out, help them discover their passion."

Through his outreach, Harrington got to know many of the riders at Annadel.

"There weren't many people who didn't know who Mark was," Brewer said.

Harrington was friends with all kinds of bicyclists. To him, the sport seemed to be all about the camaraderie, Brewer said.

"Most of us wear specially designed clothing, jerseys," he said. "Mark's jersey of choice was a button-down, blue and white striped dress shirt. He said it kept him cool."

The group is planning a memorial ride on Jan. 11 for Harrington. Brewer just purchased a blue and white, button-down shirt to wear in his honor.

Heart problems ran in Harrington's family and he suffered a heart attack earlier in the year, on Feb. 10, also at Annadel. He was rescued by helicopter and took the incident "as a point of transformation," said Vaneza Harrington.

"He didn't waste a second of his life from that point on," she said. "He was someone I think would want to be remembered as full of life."

"He'd be somewhere like the mall, and if he felt the need to dance, he'd just grab you and start dancing," she added.

Harrington recovered quickly from his first heart attack and remained active in the months that followed. He'd go out folk and swing dancing for hours at a time, Vaneza Harrington said. He also took up playing the ukulele recently.

He turned 63 on Dec. 1, celebrating with a party and dancing. "He was very happy that night," Vaneza Harrington said.

Mark Harrington, who was planning to retire soon from his job of 23 years as a safety engineer with the California Division of Occupational Safety and Health (Cal/OSHA), planned to volunteer extensively with the American Red Cross. He was attending training so that he could travel to different parts of the world as a volunteer.

"He was very adventurous; a world traveler," said Vaneza Harrington, adding that he had visited about 45 different countries. In the summer, he went on a trip with his family to Thailand. After his death, people from places like Turkey and Belgium reached out to send their condolences.

It was while in Peru in 1986 that he met his wife, Ely, in a market place. They had three children and lived in Santa Rosa for the last 20 years.

Harrington is survived by those children, Vaneza, Adriana and Danyel, and by his wife.

A memorial is planned for Harrington at 11 a.m. Saturday at Pleasant Hills Memorial Park in Sebastopol. Instead of flowers, Harrington's family asks that donations be made to the American Red Cross. The Annadel Mountain Biking Group will hold a ride in Harrington's honor on Jan. 11. at Annadel. Anyone wishing to participate can visit the group's Facebook page to learn more.