The arrivals all at Philadelphia's 30th Street Station was pitch black on Sunday after a power outage hit the train hub.
Travelers made their way through the soaring hall using flashlights on their smartphones to find their way.
The outage lasted for several hours on Sunday. PECO said the outage was resolved early Monday morning, but did not share a cause.
It's not clear if Amtrak service was affected. SEPTA said its trains were not stopped by the outage.