My husband and I are considering a five day trip to Philadelphia in June. We would fly in and stay in the downtown area near most of the attractions. However, we would also like to visit Valley Forge, Longwood Gardens, and perhaps Winterthur. Would it be possible to make these side trips using public transit (train, bus) so we wouldn't have to rent a car?

We are both pretty fit and used to walking fairly long distances, so that would not be a problem.

While you could take a taxi to get to Winterthur and/or Longwood Gardens from the Wilmington Amtrack station, it might be difficult to do both in a single day this way, and I think it would be much easier with a rental car. With a car, you could hit one in the morning and another in the afternoon and still get back to Philadelphia for a late dinner.

Ditto for Valley Forge. It's reachable by SEPTA bus, but then seeing the actual park is almost impossible without a car. It's a huge park, and there's no internal transportation.

I live outside of Phila. in the general area of those places. I'm pro-public transit, but I think it would be very difficult without a car.

I absolutely recommend mass transit for sites WITHIN the city of Philadelphia. For the three sites you mention, a car is your best bet. As eberko noted, you could IN THEORY visit Valley Forge using mass transit (rental bikes would also be nice), but a car is almost mandatory to see it within a moderate amount of time.

Suggest you go the car-rental route and split the time thusly: Longwood and Winterthur in one day, VF the other day.

I think for the L/W day, I'd start out at Winterthur, and end the day at Longwood.

For VF, you can start out in the a.m. and spend the day, with maybe a side trip to the King of Prussia Mall.