Columbia, SC to American University buses and trains from $35

Or, see buses and trains from American University to Columbia, SC.
Here are some trips other travelers have found on Routefriend.
10h 30m
0 stops
15h 31m
2 stops
Amtrak Megabus
13h 37m
1 stop
Megabus Amtrak
11h 6m
0 stops