Lying at the head of the St Mary River, Sault St Marie is unavoidable for any vessel transiting between Lake Huron and Lake Superior. There are small cities on both the US and Canadian side of the river at Sault St Marie and both have marinas close to the locks.

The marina on the US side is run by the Michigan Parks Service and like their other marinas is immaculately kept and run with full facilities and a fuel pontoon. There are aso courtesy bicycles available for those wishing to explore further afield or make a trip to the supermarket which lies on the edge of town.

Although it is said that Sault Ste Mrie has seen better days, the city is making strenuous efforts to market itself as a tourist destination with the St Marys River and Locks as the key attraction. The historic waterfront is well worth walking along and the downtown area is bustiling with bars and restaurants, some of which are excellent. For anyone who has travelled this far into the St Lawrence Waterway system then the visitor centre at the Locks is a must see attraction with a wealth of fascinating well presented information on the history and current operation of the seaway.

There are 4 parallel locks which handle the 21ft rise from the St Mary's River into Lake Superior, 3 on the US side and one on the Canadian. There is no charge for transiting any of the locks although pleasure craft are strongly encouraged to use the smaller Canadian locks which are open from 0900 to 2100. You can call the Canadian locks (Callsign VDX23) on Channel 14, ideally 20 minutes before arrival so that they have time to prepeare the lock for you. The 3 locks on the US side are open 24 hours a day and are primarily for the use by the huge bulk carriers. They are far more intimidating and turbulent than the Canadian locks and the only reason for a pleasure craft to use these would be if you needed to transit outside of the Canadian lock opening times. It should be noted that you do not need to clear in and out of Canadian waters simply to transit the Canadian locks and vice versa.