Point Porphyry is a stretch of land that extends southeast from the Canadian mainland some 35 miles northeast of Thunder Bay, Ontario. The peninsula encloses Black Bay. Just off the end of the peninsula lies Edward Island. Porphyry Point Light is located on the south end of Edward Island and marks the entrance to Black Bay. The point receives its name from the unique rock which forms the point. Porphyry stone is a volcanic rock formed from a slow cooling process of igneous material.

The first lighthouse was established here in 1873 and was the second Canadian light on Lake Superior. It was a square, white wooden building that was 36 feet high.

The present light tower dates from 1960. It is a 48-foot high cylindrical tower that is supported by an iron skeletal framework. One side of the framework is covered with slats to serve as a day mark. An octagonal lantern tops the structure and has a focal plane 82 feet above Lake Superior.

A pair of two-story dwellings, a fog signal building, and a group of smaller structures, all are painted white and have red roofs. A bank of modern free-standing fog horns are located outside the fog signal building.

The automated light is an active aid to navigation and not open to the public. It can only be viewed by boat.