How do I as a civilian come visit a friend in the hospital? (Switchboard transferred me to the Visitirs Center, but no one ever answered.)

Judith Presson is correct, your military friend has to request a pass for you and when you show up they may send someone along as an escort to help you get to the hospital on base and then back again to the gate when your visit is over. I know this because I'm an Air Force Veteran with 3 brothers who are serving now, one as a Army National Guardsman, one in the Air Force and the third an Army Airborne Ranger.

The visitors center is the only way that I know of to get a pass. Your friend might be able to sponsor you