The film is set in San Francisco, but was filmed in Pittsburgh. They used Grant Street in downtown Pittsburgh, because it is a brick road like many of the roads in San Francisco. Also, the front of the hospital is One Mellon Bank Center located on Grant Street, the same building in the helicopter scene of सडन डेथ (1995).
In addition to some of the scenes filmed in Pittsburgh, an elaborate set was constructed in a vacant hangar at what is now known as the San Bernardino International Airport, what used to be Norton Air Force Base. The prison and the hospital were three stories high, and were connected by the concourse seen in the movie.
It was filmed in 1996 since it was originally intended to be released as a late summer movie for 1997.