corridor class 

Standing or sitting in the sections between carriages on a busy train, 'cos all the seats are taken.
Usually on an unplanned long-distance trip, where the seats are all booked in advance.
About as far from first class as you can get without going outside the train.

After missing the train we'd booked seats on, we had to travel corridor class until we got to Birmingham.

corridor class by Blue Jack December 9, 2008

Cass Corridor 

A low-rent Detroit neighborhood north of downtown home to many addicts, winos, and homeless. More importantly, it is where most of the city's artists, musicians, etc. live, and most of the city's more interesting restaurants, bars, galleries, and shops are there.

Resembles pre-gentrified Greenwich, Lower East Side, or Brooklyn in NYC, except probably seedier.

Dude, I got hit up for change in front of Avalon Bread, Idle Kids, AND Traffic Jam.

That's life in the corridor, man. You got the E?

Cass Corridor by Cassie C. September 8, 2005