MARC will run weekend trains between Washington and Baltimore for the first time starting Saturday , marking the biggest expansion of Maryland’s commuter rail system in a decade.

Penn Line trains will run nine round trips on Saturdays and six round trips on Sundays. The new weekend schedule is available at

MARC riders have long called for train service for people who work weekends and for those trying to reach Baltimore-Washington International Marshall Airport.

“This has been a long time coming for MARC riders,” said Rafi Guroian, who chairs MARC’s Riders Advisory Council.

Robert Smith, head of the Maryland Transit Administration, said MARC expects to pick up many of the 6,000 weekend passengers who have been riding Amtrak between Washington and Baltimore.

“This is something our customers have been clamoring for,” Smith said.

MARC’s weekend fares will be the same as on weekdays: $7 each way between Washington’s Union Station and Baltimore’s Penn Station, compared with $16 to more than $70 on Amtrak.

Weekly and monthly MARC passes will be honored on weekends, state officials said.

Stations with weekend stops include Union Station, New Carrollton, Bowie, Odenton, BWI, Halethorpe, West Baltimore and Penn Station. Some trains will also serve Martin State Airport.

Guroian said he thinks weekend trains will attract people who don’t regularly take MARC, including tourists and BWI travelers who want to avoid paying for a rental car or parking in Washington or Baltimore.

“There will now be an affordable way to get between Baltimore, BWI and Washington on the weekends without having to drive,” Guroian said.

BWI officials say airlines, particularly international carriers that serve European airports with rail service, have asked repeatedly for seven-day MARC service. BWI passengers take a shuttle bus one mile between the BWI rail station and the airport terminals.

“To [the airlines], it’s natural, and they’re looking for it,” said Paul J. Wiedefeld, executive director of the Maryland Aviation Administration.

The weekend rail service, which is expected to cost $8 million a year, will be funded through increased state taxation of gasoline, officials said. The added tax burden — motorists are expected to pay 13 to 20 cents more per gallon by mid-2016 — is projected to generate $4.4 billion for new transportation projects over the next six years.

Smith said no weekend service is planned for MARC’s Brunswick or Camden lines in the next six-year budget.

“We identified [weekend] demand on the Washington to Baltimore line,” Smith said. “We’ll need to continue to measure the demand on the other lines.”

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