Thirty-five Alexandria residents walked out of a crowded City Council meeting yesterday proud that, after three years of labor, they had just given birth to a park.

"I'm extremely happy," said Ordell Olson, one resident who had attended many of the community's 99 meetings about proposals to create a city park in the Holmes Run area. "It's one of the last open spaces in the West End."

The City Council voted unanimously to purchase 3.5 acres of vacant land near Landmark Shopping Center and begin plans for the park. After the $1.5 million purchase of the lot at Duke Street and Holmes Run Parkway was approved, the council said it would begin negotiating for five smaller lots to expand the green space.

"Quite probably," Mayor Charles E. Beatley said, the new park will include the city's fourth public library. Discussions about the library will begin in the next few months, he said.

Many of residents from the Condo Canyon, as the valley around Landmark is known, told the council that Old Town is not the only place in the city that deserves a park. "We have paid for the Old Town waterfront, but now the city must look to the area that is the fastest growing," said John A. Cutler, head of a Holmes Run committee that sought the park.

"It's time we got our share," Olson said. "We want to ride our bikes and take walks in our own neighborhood."

The new park is scheduled to be completed with a pond, park benches, and picnic areas by the end of next year. Evergreen trees, a playground and a bike trail will be added later. If the library is approved this year, according to the Holmes Run Committee report, it will begin lending books by 1991.

"These people have done a lot of work on this," said council member Robert C. Calhoun. "It's a well-thought-out plan."

"We want parks and libraries where the people are," said Vice Mayor Patsy Ticer.

But at least one person, G. Hepnern, the owner of Duke's Car Wash at 5015 Duke St., was not thrilled with the idea of the park. His business stands on one of the five additional sites the council is eyeing for Holmes Run Park.