Originally Posted by toomanybooks

I found this in a web search:

"The hospital who`s exterior is seen on the show is the University of
Illinois Hospital at 1720 W. Taylor Street, which is part of the
University of Illinois Medical School. (This is not to be confused
with the University of Illinois at Chicago (UIC) Hospital, which
is eight blocks to the east). The U of I hospital is about a
half-mile from the real Cook County Hospital."

Originally Posted by Olton Hall

With the exception of obvious on locations shots, it's almost all a set WB studios, patched asphalt and all. It's part of the WB studios tour. The detail they go through on the building exteriors and the L are amazing.
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