Letchworth is very nice. If you go south on 390 /pa 15s when you get into Pa stop at the visitor center ( rest stop) they have lots of good info on PA. Traveling south of the rest stop is Rt 6 and the PA Grand Canyon ( Wellsboro) .Going west of Wellsboro on Rt 6 is the PA Lumber Museum( CC Camp info). Getting back on 15 south will take you pass the Little League Museum in Williamsport. Rt 15 s will also take you to Gettysburg. Antietam is also a nice to check out. BTW Pa turnpike is very expensive. Have a nice trip and Safe Travel.