Many cities have there under ground. You would think of Seattle or Portland. There is also underground Tacoma bars and courthouse underground. Very few have been granted permission to go down ant see it. The football field in the movie 10 things in hate about you. Is one of the access points.
There is also underground in Astoria Oregon. I have a theory that a small town in eastern Washington has one to. I've had my suspicions for 30 years. I will let you know
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