Security lines were moving quickly at the Philadelphia International Airport despite a noticeable spike in the presence of security, with more police and TSA agents constantly patrolling.
Those that were there are happy to be coming home.
Sarah Watkins of Rittenhouse Square was wearing the jacket she got for running the race when we caught up with her. She says she finished the race about an hour before the bomb went off.
"I was just sitting in Boston Garden with my boyfriend and we heard [the bomb] go off," said Watkins.
Sarah, like many runners, says she is still trying to process what happened, and how close she was to the danger.
"It is someone's loved one. You know? And? it's hard," said Sarah.
The weight of the Boston tragedy weighed down bustling travelers in 30th Street Station Tuesday morning as Police armed with assault rifles and with trained dogs by their side stood watch.
North Carolina resident Rick Smith tells Action News, "A lot of concerns around the safety. Obviously the policemen are here - dogs are out."
Jim Kebert of Arizona says, "It's a reminder it can happen at any time, at any place."
Boston is also high on the minds of commuters who pass our nation's landmarks on Independence Mall.
Guillermo Tellez of West Chester explained how he is coping with the tragedy, saying, "I try not to think about it. You know, just take it day by day."
But Philadelphia city officials want you to think about the Boston Marathon bombing.
Yesterday Police Commissioner Charles Ramsey called on the public to be alert, whether coming to the city by NJ Transit, Amtrak, car or bus.
But plenty say they feel safe and are moving forward, but not putting the tragedy out of their minds.
Overbrook resident Anne Marie Strawberry summed up that sentiment, saying, "You can't live in fear. You have to go about your daily business and just pray for the best."