The
Shanghai Tunnel is a bar in
Portland, Oregon. It is a dark, divey bar, although they have been fixing the place up quite a bit. The upstairs is
relatively empty, as most people drink their drinks and
smoke their cigarettes downstairs, in the tunnel.
The origin of the name is more interesting, perhaps, than the bar itself. In Portland, there is a network of tunnels running under the city. About 100-150 years ago, there used to be trap doors in various saloons, and unsuspecting patrons would become victims of "shanghaiing." They would be stolen, for lack of a better word, and taken through the tunnels down to the river where they were forced to work on boats.
This is how Portland came to be known as one of the most dangerous ports in the world.
a rather informative web page on the subject can be found at: http://members.tripod.com/cgs-mthood/shanghai_tunnels.htm