At first glance, it looks like the parking area for a very popular party. Rows of vehicles line the paved lot and overflow onto the grass and along the curb for blocks.

But it's no party. It is the commuter parking lot for the Virginia Railway Express in Manassas Park, where the current spaces--all 300 of them--are easily filled by 9 a.m. The remedy, officials say, is to add 300 more.

"It's what this place needs," said John Shelton, a Manassas resident who commutes daily to the District. "If you ride the last train, which I do, then you have to park somewhere else."

In an unanimous vote, the City Council recently approved the parking expansion, though a formal site plan for the project is still being developed. Early estimations indicate the lot will cost more than $1 million. Construction should begin next year and finish 15 months later.

Meanwhile, officials have agreed to shuttle commuters to and from the commuter lot from various bus stations around town, which "may take the edge off the parking situation," said Al Harf, executive director of the Potomac and Rappahannock Transportation Commission (PRTC), a parent of VRE.

"The fact that it's filled might discourage people from using [the lot]," said City Manager David W. Reynal. "And we would like to have additional people come into the city. We really want to encourage people to commute."

The number of people using VRE continues to rise, with ridership reaching an all-time high of 8,500 Wednesday, Harf said. The average at the Manassas Park station for September was 315 people. But the number is deceptive, Harf said, because ridership is heaviest during the week and almost always much lower on Fridays and Mondays.

"During the week we've got an excess of 350 people riding," he said.

Also, because many riders don't car pool, the 300-space lot fills quickly, Harf said. In addition many people from outside Manassas Park use the lot, which is free, he said.

On a recent evening at the commuter lot, the setting sun glared off the rows of metal, leaving an array of shadows on the sidewalk. The train whistled, slowed to a stop and dozens of professionally dressed men and women stepped forward. Within minutes, a steady line of cars waited to exit the lot.

"It seems the overflow has really happened over the last couple of months," said Tim Valentine, a Prince William County resident who has been using the rail service for 14 months. "I guess people were just getting tired of making the long drive to the office."