Marcus Passage is a stretch of saltwater on the North Coast region of British Columbia, Canada, offshore from the mouth of the Skeena River, south and west of Smith Island.

The south side of Marcus Passage is defined by an extensive drying bank called Base Sand (locally known as Wilson Bar).

[3] Two shoals obstruct Marcus Passage, the first extends from De Horsey Passage to Base Sand, the second extends from De Horsey Island to Kennedy Island.

Sand waves with amplitudes of 1.6 metres (5 ft 3 in) are known on these shoals.

This article about a location on the North Coast of British Columbia, Canada is a stub.