FREMONT — Unlike water, community mixes with oil beautifully.

Or so says the Mission San Jose Chamber of Commerce, sponsor of the fifth annual Olive Festival taking place today.

Organizers founded the one-day event in 2001 to bring the community and local businesses together, said Connie Andrade, a chamber board member who worked on the first festival.

"It's a fun day and a great place to take a family. There are things to do for all ages," she said.

The daylong homage to the oval Mediterranean fruit celebrates all things olive — with a nod to Mission San Jose.

Vendors will sell theme items such as olive oil soap, and experts are scheduled to give a presentation on the history and production of olive oil, festival chairwoman Gael Stewart said. Even a lighthearted "Olive Costume Contest" will be held for kids. Other scheduled kids' activities include face-painting and artwork.

"It's a small, unique festival," Stewart said.

In addition to food booths and music ranging from easy-listening jazz to a "Grateful Dead-type" rock band, a wine-tasting garden and three food demonstrations will be featured.

Last year's festival drew more than 2,000 people to the land where the Dominican Sisters, a local Roman Catholic order of nuns, annually harvest olives and produce their own olive oil, Andrade said. The property is behind the Historic Old Mission San Jose Museum.

"With its wonderful ambiance, it's a special place," Andrade said. "The grounds are absolutely beautiful."

Festival planners say they chose the location specifically to create a new neighborhood activity that highlights Mission San Jose's past.

One of 21 Spanish missions started in California, Mission San Jose was founded in 1797 in an area once long inhabited by Ohlone Indians. The Mission San Jose district once was its own town. It became a part of Fremont when the city incorporated in 1956.

But the neighborhood hasn't lost its small-town flavor, Stewart said, and the festival reflects that spirit.

"It's a quaint, charming, quiet area," she said. "It's our last bastion of old Americana."