Mr. Zwierlein spent decades as a farrier in Woodside, shoeing many of the horses in town until he retired in 1991.
He also served a term on the Woodside Town Council, for a short time owned the Hitchrack saloon, was a volunteer firefighter and a founding member of the San Mateo County Horsemen's Association, running the Junior Rodeo for them for 31 years.
He also served on Woodside's History Committee and was a road commissioner.
Mr. Zwierlein was a third-generation native Californian, and his grandfather, William Pajaro King, was the first white child born in Watsonville, family members said.
In an interview on Oct. 19, Mr. Zwierlein reminisced about his life.
He was born in Palo Alto on Dec. 24, 1926, and attended Addison, Lytton, Channing and Palo Alto High schools. His mother was Elfleda King Zwierlein and his father, Edmund Zwierlein, owned shoe stores.
The family moved to Woodside in 1941 and the teenage Zwierlein went to work for Holt's Country Store afternoons and weekends. Mr. Zwierlein said he worked at the Holt gas station, ice house and the soda fountain — all at the same time. "It wasn't that busy, so basically I could handle all three," Mr. Zwierlein said.
When he moved to Woodside, a decade and a half before the town was incorporated, the population was under 500, he said. In those days, it was considered a building boom, he said, "if three houses were built in Woodside at one time."
Mr. Zwierlein grew up around horses and he began competing in rodeos at a young age. "I started riding calves at the age of 10," he said.
From there he progressed to steers until, at the age of 18, he could ride bulls. He also competed in bareback bronc riding and steer wrestling.
He practiced at least three or four nights a week in his father's lighted arena. "My dad had a big ring on his property. He had 10 acres on Olive Hill Lane."
From 1946 to 1952, Mr. Zwierlein competed as an amateur and was the Tri-State bareback champion of the Cowboys Association of America in 1952, when he was 26.
The next year he turned professional, the beginning of a 12-year career.
"I was a very good cowboy," he said. "I was probably one of the 10 best bronc riders in America."
He competed all over the country, sometimes in two or three rodeos in a weekend. He won in several big rodeos — and lots of small town ones.
In Madison Square Garden, at a 28-day competition, Mr. Zwierlein came in sixth out of 80 bronc riders. He placed second in bronc riding at the world's biggest one-day rodeo at the Los Angeles Coliseum, in 1956.
The rodeo days weren't all glory, though. "When I first started out I basically didn't have any money," Mr. Zwierlein said. Instead of paying for hotels and restaurant meals, he brought a sleeping bag and sandwich along.
With wins came prize money and improved traveling conditions, until finally he found himself able to "travel in a friend's airplane, a Cessna 171."
"I was probably the best bronc rider that ever came out of San Mateo County," Mr. Zwierlein said, rather matter-of-factly. In steer wrestling, "I still hold the record down at Redwood City," he said. "I have the fastest time ever recorded in the 30 years of rodeo," at 4.4 seconds.
Injuries suffered in the rodeo days, including a broken toe, ankle, elbow, left arm and ribs (twice), a wrecked knee and a fractured spine, have kept Mr. Zwierlein off horses for the past six years. "I can't touch my toes and I can't put my foot up high enough for the stirrup," he said.
The injuries weren't what got him off the rodeo circuit, though. What did? "Age. I quit at the age of 36. That's getting up there .... the average guy maybe only goes to age 28, 29 because of the injuries," Mr. Zwierlein said.
"I just got tired of driving up and down the road, and thought I'd stay home."
Staying home wasn't entirely successful, though, and at 39 he went back "because I had some of the young guys calling me a has-been and I wanted to show them that I could still do it."
He placed first in the first two rodeos and was third in the third rodeo. "At the end of the season I was selected to represent California at the finals in Reno," he said, one of only five cowboys from California. Then he retired for good.
Except ... "I still wrestled (a steer) at the Mounted Patrol at the age of 50. They asked me to fill an event," Mr. Zwierlein said. "I did it — I did very well — I threw one in 9.6 seconds — and that was the first time I'd steer wrestled in probably 12 years."
Mr. Zwierlein competed in four sports in high school — basketball, baseball, football and swimming. In Woodside, he formed a men's basketball league, soon after what is now the Sellman Gymnasium was completed.
"I played in that gym from (when) I was 21 until I was 50," he said. "We played any team that would volunteer to come up." Two memorable games were against 49er football players, which the public was charged admission to watch. "They beat us," he admits.
Others on the team included: Cliff Andrews (recently deceased); Ross Stewart, Gene Decker (a vet), Don Acker (a horseshoer), and Tom Lagerquist (an attorney who still lives in Woodside).
Mr. Zwierlein served as president of the San Mateo County Horsemen's Association in 1970 and 1973, a position his father Ed had held before him. Ed Zwierlein was a professional baseball player, announced at the Fourth of July rodeos, and was twice captain of the Mounted Patrol.
The Zwierlein picnic area in Huddart Park is named after Ed Zwierlein, in honor of his work promoting recreation, including serving on the Riding and Hiking Trails Committee of the state parks commission.
Harold Zwierlein always loved to tell a good story. Some of his oft-repeated favorites include the time he rode his horse into the Pioneer Hotel bar at the age of 16; the time he was baptized by an old classmate who had become a preacher who was just supposed to be baptizing his daughter, or the time a bucking bronco fell on him, fracturing his spine, and the rodeo doctor, who Mr. Zwierlein suspected was actually a vet, wanted to shoot him up with morphine and send him back into the arena.
Mr. Zwierlein said he led a good life. "I've been a very, very lucky person," he said. "I had good parents. Moved up here to Woodside. Went to Palo Alto High School, I enjoyed that."
He was able to spend his working life outdoors, he said, adding: "I don't think I've had too many bad days in my life."
Mr. Zwierlein is survived by his wife, Irenne Zwierlein of Woodside; his daughter, Carolyn of Ben Lomond; son Kurt; granddaughters Allison and Ashley of Acampo; his older brother, Edward Zwierlein of Palo Alto; and three stepchildren, Garrett Auger, Danniel Auger and Michelle Zimmer, who all live nearby with their children, Garry Zimmer, Andrew Mendez, Phoenixx Auger, Christopher Zimmer, Shelby Zimmer, Hailee Auger, Preston Auger, Kylie Auger, and Kaitlynn Lane.
Memorial donations may be made to Sutter VNA & Hospice (suttervnaandhospice.org) or the San Mateo County Horseman's Association (sncha.org).
Barbara Wood is a freelance writer, photographer and gardener from Woodside
Memorial services will be held at the Mounted Patrol Grounds, 521 Kings Mountain Road in Woodside, at 2 p.m. Saturday, Nov. 20.
Correction: An earlier version of this story mistakenly listed Nora Whiting among the children of Mr. Zwierlein's step-children. Nora is the daughter of Steve Whiting, Harold's former son-in-law, who remained close to Mr. Zwierlein, who thought proudly of Nora as his own grandchild, family members said.