Essex County sits in the northeastern corner of New Jersey and holds some of the oldest residential housing stock in the state. Newark, Bloomfield, Belleville, Irvington, and Montclair all contain large numbers of pre-1950 homes, many of which were built when knob-and-tube wiring was the standard installation method. The county's housing mix runs from dense urban rowhouses and two-family homes in Newark and East Orange to the larger single-family Colonials and Tudors of Maplewood, Millburn, and Livingston. Electrical systems in the older urban stock often include original fuse boxes, undersized service entrances, and wiring that has been patched by multiple hands over decades without a full system inspection.