The strike began early Saturday after negotiations between the Southeast Pennsylvania Transportation Authority and two unions failed to reach a new contract deal.
Subways, trolleys and buses operated by SEPTA will continue to run.
The real impact of the strike is expected to be felt Monday.
SEPTA's regional rails carry about 60,000 commuters on a typical workday.
SEPTA is planning to add extra subway and trolley cars to help with expected heavier demand.
DART said Friday it will provide bus service between Newark and Philadelphia making stops at A-T-and-T station and the sports complex at Broad and Pattison Streets.
Bus service will run Monday through Friday only and will not match the train schedule, but it will run during peak hours. You can check out the schedule by clicking here.
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