Two days of celebration begin tomorrow in the annual Feast of the Holy Ghost. Islanders of Portuguese heritage and their friends will party, dine and parade in a festival whose traditions date back more than half a century.

"This is our heritage," said Bobbie Ann Gibson of Oak Bluffs, president of the Holy Ghost Association.

The center of festivities is the Portuguese American Club on the corner of Vineyard and County avenues in Oak Bluffs. While preparations have been going on for days, the event begins tomorrow at 5 p.m. with a gathering for food and music. An auction begins at 7:30 p.m. There will be breads and lobsters for bidding, along with other donated goods. "It's like a block party," said Mrs. Gibson.

Sopa will be for sale. The traditional soup is filled with the familiar ingredients - kale, linguica and chourico, a hot pork sausage from Portugal seasoned with paprika, pepper, garlic and other spices.

For more traditional American tastes, there will be hot dogs and hamburgers on the grill. "We have carnival games for kids. It's a big family event," Mrs. Gibson said.

Much of the weekend holiday is tied to traditions going back to Portugal and dating back in Vineyard history. There will also be a mix of contemporary sounds. Ray Frazio is bringing The Ray Band for dancing into the night.

This is Tricia Bergeron's 13th year as mardon, the top organizer for the event, and she has plenty of rich festival memories. "Why do I do it? It is family heritage. My earliest memory of it is when I was a child. I remember all the Portuguese people coming off the ferry. It was either the Nobska or the Islander. They were dressed in black. They brought their goats over," she said.

"This is a reunion," said Mrs. Gibson.

Mrs. Gibson's memory goes back, too. "My parents, William and Nellie Amaral of Oak Bluffs, were among those who originated the club. My involvement is a tribute to them," she said. She and her sister, Catherine Deese, will share some of the work. "Years ago they had it on different days. Then we decided to have it on the third weekend of July. Now everyone knows when it's held," Mrs. Gibson said.

It wasn't always held in Oak Bluffs. Vineyard Gazette stories go back to the 1940s when it was held in Vineyard Haven. In 1945, music was provided by the Bay State Band of New Bedford. In that year, 300 loaves of Portuguese sweet bread were baked for the event.

For tomorrow's celebration, festival organizers will acquire 125 three-pound lobsters. To cook the famous sopa, they will use 300 pounds of linguica, 180 pounds of chourico and hundreds of pounds of onions, cabbages and potatoes. The sopa costs money on Saturday, but on Sunday it is free.

Tomorrow night's festivities will be contemporary, too. The Ray Band includes singer Christine Box, Brian Weiland as lead guitarist, Tom Howland on the bass and Chas Griffiths on drums. They are expected to play well into the night and to be joined by guest singer Lenny Baker of Sha Na Na.

David Araujo, former Tisbury selectman, will be the auctioneer and will step in during band breaks.

The celebration resumes on Sunday at 11:30 a.m. at the Steamship Authority wharf. There will be greetings for the visitors from afar. The Bay State Band is coming to join in the parade. There will be Portuguese folk dancers from Fall River. Hundreds of participants will march up Circuit avenue to Our Lady Star of the Sea Church. There, a silver crown representing Queen Isabella's own crown will be blessed.

The crown will be worn by Lily Gazaille of Edgartown. She will be dressed as the Portuguese queen.

The holiday event commemorates Queen Isabella, who lived from 1271 to 1336 and was beloved for her charity to the poor.

The parade continues up Vineyard avenue to Sacred Heart Cemetery, where a memorial wreath will be placed. The parade ends back at the Holy Ghost Association property, where the party begins anew and continues until 6 p.m.

In the afternoon, the most significant part of the auction begins. In honor of the Queen Isabella story, the sopa is served for free. "Sunday is the Islanders' day," Miss Bergeron said. The bidding items will include dinners at such popular restaurants such as Atria and Opus. Massages will be offered. Patrons can bid on jewelry, wampum and pizzas. Even homemade sweaters for children, made especially for the auction, will be offered.

Miss Bergeron said organizers are expecting to see between 3,000 and 4,000 participants. It promises to be the biggest gathering on the Island until the Agricultural Fair in August.