For Michael McCullaugh, born in Ireland, Sonoma County is not only home, but a vivid reminder of his native country.
"When I ride my bike out to the seashore this time of year, it's pretty much like Ireland," he said. "It's all green."
Emerging from their small emerald island, the Irish have roamed the world, so it's not surprising to find them in Sonoma County.
"There's always an Irish community wherever you go, so you always have a sense of family," said Catherine Crotty of Rohnert Park, a native of Ballinasloe in County Galway.
It's hard to find precise numbers on Irish immigrants living in Sonoma County, but it is true that there are more than 63,000 people in the county who report Irish ancestry, according to the latest U.S. Census estimate.
"There's a large Irish community in Petaluma, and it's close-knit," said Crotty, 55, who came to the U.S. with her family when she was 10, and now teaches English and beginning computer skills at the Petaluma Adult School.
And, of course, everyone is Irish on St. Partick's Day. Some Irish immigrants say the holiday is a much bigger event in the United States than it ever was in the old country.
"It was really just another day for us," said McCullaugh, 52, who grew up Catholic, but surrounded by a Protestant majority, in County Armagh in Northern Ireland.
"I remember my first St. Patrick's Day in the states. It was in San Francisco. I went down to the parade and everything was green. There was even green beer, and corned beef and cabbage," he said.
"That was really strange to me," said McCullaugh, co-owner of the Aqus Cafe in Petaluma and the Redwood Cafe in Cotati.