Layover in PHL visit into city.
 

My wife and I will be going to Dublin from Tampa August 18 with a 5 hour layover in PHL landing at 2:40pm. Flight leaves at 8:25pm In the past we had a long layover in Boston, we took the subway into Boston and walked around and had lunch. Can we do this in Philadelphia? Maybe a taxi or uber? We have never been to Philadelphia and would like to see the historic sites.
We could also get into PHL earlier and have a 7 hour layover to give us more time in Philadelphia.
Thank you for your help.

There is a train at the airport that can take you to center city Philadelphia.

SEPTA Regional Rail. SEPTA’s Airport Line stops at all major Philadelphia International Airport terminals and is just a 25 minute ride from Center City with one intermediate stop.

Or you could take a taxi of Uber or Lift.