Gettysburg, PA to Princeton University buses and trains from $33

Or, see buses and trains from Princeton University to Gettysburg, PA.
Here are some trips other travelers have found on Routefriend.
$33
3h 30m
3 stops
Amtrak NJTransit
$43
2h 31m
0 stops
Amtrak
$46
3h 10m
1 stop
Amtrak NJTransit
$48
3h 30m
2 stops
Amtrak NJTransit
$59
4h 18m
2 stops
Amtrak NJTransit
$68
5h 55m
1 stop
Amtrak Megabus
$69
4h 30m
2 stops
Amtrak NJTransit
$73
4h 57m
2 stops
Amtrak NJTransit
$75
3h 49m
2 stops
Amtrak NJTransit