The Northport Back Range is a square, wooden, tapered range light, 13.6 m (44.6 ft) high with a shingled exterior. Originally an open frame tower, it was enclosed in 1903. It was raised 3.3 m (11 feet) in 1887 and 1.8 m (6 feet) in 1970. The result is a curious combination of sloped base and straight top. Simple with no decorative details, the range is painted white with red trim and a vertical red stripe extending downward. It was originally a front range light until 1962 when a new front range was constructed. It has been moved a number of times to align with the channel.