As an estimated 50,000 participants in Saturday's Women's March on Philadelphia made their way into the city, some encountered an obstacle their sister marchers across the country did not have to contend with: SEPTA.

Running on a regular Saturday schedule, the Regional Rail system was overwhelmed on some lines by the swell of marchers, who far exceeded early turnout predictions of 20,000 to 30,000. Riders reported delays on Twitter and complained of trains breezing past their platforms without stopping.

SEPTA put eight extra trains on the tracks in response to delays, and already had two or three more trains than usual running on most lines, said spokeswoman Carla Showell-Lee.

On Twitter, rider complaints abounded. Users reported delays or trains bypassing stations, and wondered why SEPTA had not prepared for the crowds, which were compounded by another big draw - the Philly Home Show at the Convention Center.

"@SEPTA just blew past 30th Street station. I'd complain to @SEPTA_SOCIAL but it won't go anywhere. Public transport the public can't use," tweeted user Kate Allison.

Showell-Lee said the agency knew about the march, had anticipated a large crowd, and would not have done anything differently to prepare for the day.

"You can anticipate and prepare and prep, but you can never guess at a spike even if you prepare," she said Saturday evening. "When you have something of this magnitude where . . . women and men came out in droves, that just takes it to a whole [new] level."

She could not give an estimate of how many riders took SEPTA on Saturday but said it was "considerably more" than normal. Ridership was particularly heavy on the West Trenton, Paoli-Thorndale, Media-Elwyn, and Lansdale-Doylestown lines.

At Suburban Station, SEPTA began collecting fares on the platform at around 2 p.m. and continued until 6 p.m. due to overcrowding on trains.

Trains were running late all day, with peak ridership from 9 to 11 a.m. and 3:30 to 5:30 p.m. Regular service had been restored to all lines by 6:40 p.m., according to SEPTA.

A signal problem on the West Trenton line also delayed trains Saturday.

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