I think Concorse B is pretty much Southwest. I do not know who uses C. The Southwest ticket counter is between B&C. After I got my Boarding Pass, I was told to go to my right, to B. The line for security was close to half way to C, and about 6 people deep. An airport personel was at the end of the line telling people to pass through security at C, and then walk through the parallel tunnel just inside security back to B. There was no line at C, as no one else followed the advice.

This tunnel is not on the terminal map, but neither is much of anything else.

http://www.bwiairport.com/5custasi/in_tm.shtml

So leave the Southwest ticket counter to the left(North), pass through security at C, make an immediate right, and go through the tunnel to B. The tunnel is labeled at C for gates to B. It is not labeled at B for gates to C.

[This message has been edited by slawecki (edited 04-12-2003).]