MARC said it will add more train cars to increase capacity on its weekend service between Baltimore and Washington.

The rail service, which also runs on weekdays between the two cities, was expanded in December to also run on weekends. It was the biggest expansion of Maryland’s commuter rail system in a decade.

Since the weekend service started, officials who run MARC said, it has seen such “steady growth in ridership,” that they decided to add more cars to the weekend trains. On the March 8 weekend, MARC said it saw the largest number of weekend train riders, totaling 6,530 passengers.

Starting Saturday, there will be one to two more MARC cars per train on the weekends, which will allow the trains to carry more people.

MARC currently runs nine, three-car trains on Saturdays, and six, three-car trains on Sundays. With more cars on a train, MARC said it will increase its capacity from 389 passengers per train to a maximum of 653 passengers.

The rail service, which is run by the Maryland Transit Administration, invested $46 million to start the weekend service, officials said.