BART officials said that around 9am, a woman's shoe got stuck on one of the escalators at the Embarcadero station, according to the San Francisco Chronicle.
The woman wasn't hurt, but officials did shut down the escalator. Because of that commuters headed to a second escalator, which soon became overloaded, causing officials to shut it down as well.
That in turn led to overcrowding on the platform, so trains were ordered to skip the Embarcadero station in both directions until the crowds thinned out.
Trains resumed regular service by about 10 a.m.
for more features.