The Mount Isa Underground Hospital, constructed during March/April 1942 in the grounds of the Mount Isa District Hospital, was built by off-duty miners from Mount Isa Mines. As a wartime underground civilian hospital, built by civilians, it appears to be unique in Australia.

The underground hospital occupies an area roughly 20m square in the southeast corner of the Mount Isa Base Hospital grounds, and entry is via the Beth Anderson Museum building, which is accessed from Joan Street.

The layout of the underground hospital consists of three parallel east-west tunnels cut into shale rock, joined at their eastern ends by a 20m crosscut tunnel running north-south, forming a large reversed ‘E’. A ventilating raise is located in the intersection of the crosscut and the north tunnel, and at the rear of the crosscut opposite the north and south tunnels are two recesses for cupboards. The tunnels are of varying widths, between 2.6 to 3.5m. The south tunnel is now the entrance for visitors, while the middle tunnel is now the exit. The north tunnel is still sealed.

Before restoration, little remained of the original furnishings and medical equipment. However, between 1997 and 2001 the internal fit out was reproduced, based on photographs from 1942.