Which show was set in an actual working hospital?

"ER" is an American medical drama television series created by novelist and medical doctor Michael Crichton that aired on NBC from September 19, 1994, to April 2, 2009, with a total of 331 episodes spanning over 15 seasons. "ER" follows the inner life of the emergency room (ER) of fictional County General Hospital in Chicago, Illinois, and various critical issues faced by the room's physicians and staff. The show is the second longest-running primetime medical drama in American television history behind "Grey's Anatomy", and the 4th longest medical drama across the globe.

A typical episode centered on the ER, with most scenes set in the hospital or surrounding streets. In addition, most seasons included at least one storyline located completely outside of the ER, often outside of Chicago.