An afternoon in the country? It could be, except for those high-tension power lines, oil wells and the steady whoosh of traffic.

Melvin Hillman and his 11-year-old twins, Damon and Damian--dressed in matching gray sweat suits--walked down the hillside path and paused on the wooden bridge to gaze at the rocky stream in the breezy afternoon chill.

“We like to jump across the rocks and play here,” Damian said. The sloping green land--with its trees and covered picnic areas--is a peaceful place to “get away and relax,” his father added.

A short distance below, where the stream empties into a glistening fishing lake, ducks quacked and a few anglers put up with the cold as they watched their lines, hoping to land a catfish--which is not too hard because the lake is stocked every couple of weeks.

Wardell Garrett, who retired and moved to Los Angeles from Chicago 18 months ago, saw his fishing rod suddenly jump, but by the time he grabbed it from its metal holder the cat was off the hook.

“I thought I had my supper,” Garrett said, sporting a smile and a black beret. “He was a big one, too, but I’ll catch him another day.”

An afternoon in the country? It could be, except for those high-tension power lines atop a row of low hills, rocking-horse oil wells pumping away on the horizon, the steady whoosh of nearby La Cienega Boulevard traffic and a post card-perfect view of Century City high-rises in the distance.

“I was surprised there was so much here,” said Hillman, recalling his discovery of the Baldwin Hills State Recreation Area while it was still under construction more than four years ago.

For Hillman and other regular visitors who live near the wilderness of hills and canyons--which stretches between La Cienega and La Brea Avenue north of Stocker Street--it is like a neighborhood park.

But what a park.

The 300 acres--once dotted with oil wells--contain two fishing lakes, hiking trails and picnic areas, an archery range, parking for 478 cars, spectacular city views and an Olympic Forest with ponds and paths that twist down a hillside.

The forest commemorates not only the 1984 Olympic games--there’s one tree from each of the 140 nations that participated--but marks the time that the park site served as the Olympic Village housing athletes during the 1932 games, which also were held in Los Angeles.

Woodrow W. Williams said he has come to the park almost every day since it opened in November, 1983, to fish and to walk. “There’s baseball, tennis, volleyball and joggers all over the place,” he said, adding that rabbits, quail and pheasant may be seen up in the hills.

According to the office of Los Angeles County Supervisor Kenneth Hahn, the veteran supervisor got the idea for the park 20 years ago when the land was still producing oil. County plans for a park were derailed by Proposition 13, but the state later came through with $27.6 million in bond money to build the park, which is free and open year-round. There are plans to add 176 more acres as oil production on surrounding land is phased out.

“Ultimately, this all will run dry and we don’t want to see the land turned into businesses and condominiums,” said Hahn spokesman Dan Wolf. “We owe it to the future to keep open space.”

A bit of a secret at first, the park--which is rather inconspicuous when viewed from busy La Cienega--has gained fame, and on a sunny weekend day, it attracts thousands, according to regular visitors and park patrol officers.

“On a major holiday, like Memorial Day, Fourth of July or Labor Day, it’s packed,” said Wallis Jones, who has been on the park patrol since it started.

Jones said that the relative isolation of the land, along with regular auto patrols and the nighttime closure, has kept the recreation area largely free of crime and vandalism.

“You see gangs drive in, but they don’t stay,” he said. “People feel safe here.”

What: Baldwin Hills State Recreation Area.

Where: 4100 S. La Cienega Blvd., Baldwin Hills.

When: Sunrise to sunset, every day.

Admission: Free.