Here are some shots of building of Norristown State Hospital, built in 1879. The hospital was Pennsylvania's first state inpatient psychiatric facility and is now the only one in southeastern Pennsylvania. The hospital was built in the "cottage model" (see Asylum architecture) with a number of separate structures. The hospital advocated moral therapy and limited restraint. In the mid twentieth century, there were over 4000 patients. The hospital now serves 307 patients in General Psychiatry and 120 in Forensic Psychiatry.
It is one of many buildings on the property, but it is the only one that lies abandoned. The rest of the asylum is fully functional as far as I can tell... the majority of the "older" buildings have all been demolished. This is the only old building still standing.
Some old photos--> www.rootsweb.ancestry.com/~asylums/norri stown_pa/index.html
(click on image for more! :-)