St. Lawrence Seaway
Inland lake · Area 517.7 km² · 24 harbours
Show on mapPlan route from Brockville Yacht Club
St. Lawrence Seaway is an inland lake with no waterway to the sea (Canada). Area 517.7 km². Sailseer covers 24 harbours, including Brockville Yacht Club, Sandra Lawn Marina, St. Lawrence Marina, Tall Ships Landing Marina, Brennan Marine.
Rules on the lake
St. Lawrence Seaway: The St. Lawrence Seaway from Montréal to Lake Ontario is operated by the Canadian St. Lawrence Seaway Management Corporation (five locks) and the US Great Lakes St. Lawrence Seaway Development Corporation (Snell and Eisenhower). Pleasure craft in 2026 from 8 to 10 May and from 15 May to 18 October; the Canadian locks at fixed times with online booking, CAD 25 per lock (Beauharnois both CAD 50), Snell and Eisenhower on demand for USD 30 each. At least 6 m and 900 kg, not under sail, at most 35.5 m above the water, life jackets for everyone. The river is the border between Canada and the USA: boats only passing through do not report; anyone who lands or anchors in the other country reports at once (Canada to the CBSA, +1 888-226-7277; USA through the CBP ROAM app).
Harbours on the lake
- Brennan Marine
- Brockville Yacht Club
- Carnegie Bay Marina
- Clark's Marina
- Crysler Park Marina
- Gananoque Municipal Marina
- Hafen (Alexandria Bay)
- Hafen (Châteauguay)
- Hafen (Ivy Lea)
- Hafen (Ivy Lea)
- Hafen (Mallorytown Landing)
- Hafen (Ogdensburg)
- Howard's Marine of Rockport Ltd.
- Hucks Marine & Resort
- Kahnawake Marina
- Peck's Marina
- Sandra Lawn Marina
- St. Lawrence Marina
- Swan Bay Marina
- Tall Ships Landing Marina
- The Landing At Ivy Lea
- Thousand Islands Yacht Club
- Trident Yacht Club
- Village Guay marina
Formalities
Frequently asked questions
St. Lawrence Seaway: What rules apply to boats?
The St. Lawrence Seaway from Montréal to Lake Ontario is operated by the Canadian St. Lawrence Seaway Management Corporation (five locks) and the US Great Lakes St. Lawrence Seaway Development Corporation (Snell and Eisenhower). Pleasure craft in 2026 from 8 to 10 May and from 15 May to 18 October; the Canadian locks at fixed times with online booking, CAD 25 per lock (Beauharnois both CAD 50), Snell and Eisenhower on demand for USD 30 each. At least 6 m and 900 kg, not under sail, at most 35.5 m above the water, life jackets for everyone. The river is the border between Canada and the USA: boats only passing through do not report; anyone who lands or anchors in the other country reports at once (Canada to the CBSA, +1 888-226-7277; USA through the CBP ROAM app).
St. Lawrence Seaway: How big is the lake?
Area 517.7 km².
St. Lawrence Seaway: Which harbours are there?
Sailseer covers 24 harbours, including Brockville Yacht Club, Sandra Lawn Marina, St. Lawrence Marina, Tall Ships Landing Marina, Brennan Marine.