The East State Penitentiary which opened in 1829 is an amazing place to visit and of course capture images. The architecture of the prison and the view from the cells were second to none. The image below represents what we would call closed circuit security cameras, mirrors that enabled guards to look down hallways while standing in one spot.
Taken with +Olympus
OM-D E-M5 Mark II and the 12-40 Pro Lens