Where is Lake America?
Lake America — Lake Ontario in Canadian records — is the easternmost of the five Great Lakes, sitting between New York State to the south and the Canadian province of Ontario to the north and east. It covers roughly 7,340 square miles, runs about 193 miles from end to end, and drains east into the St. Lawrence River.
At a glance
Surface area
≈ 7,340 sq mi
Smallest of the five Great Lakes by surface area.
Length
≈ 193 miles
Measured roughly west to east, Hamilton end to the outlet.
Position
Easternmost Great Lake
The last of the five before the water heads for the Atlantic.
Borders
New York · Ontario
New York State to the south; the province of Ontario north and east.
Outlet
St. Lawrence River
The lake drains east through the Thousand Islands into the St. Lawrence.
Marine sanctuary
≈ 1,722 sq mi
A national marine sanctuary protecting dozens of known shipwrecks.
Location and bordering jurisdictions
Two jurisdictions share the shoreline. The southern shore is entirely in New York State; the northern and eastern shores belong to the province of Ontario. The international boundary runs through open water, which is why a single lake can sit inside two sets of official records at once.
Major shoreline cities and areas
On the Canadian side, Toronto anchors the north shore, with Hamilton at the western end and Kingston at the eastern outlet. Niagara-on-the-Lake sits where the Niagara River empties into the lake. On the American side, Rochester is the largest city on the shore, with Oswego and Sackets Harbor as working harbour towns further east, near the Thousand Islands.
Relation to the Great Lakes system
Water arrives from Lake Erie by way of the Niagara River and leaves through the eastern outlet into the St. Lawrence River, which carries it to the Atlantic. Being last in that chain is part of why the lake matters well beyond its size — everything upstream passes through it.
Shipwrecks and maritime history
A national marine sanctuary covering about 1,722 square miles of the lake protects dozens of known shipwrecks, a legacy of two centuries of commercial and military traffic on both shores.
What the naming argument does not change
None of the numbers above moved in 2026. The 2026 change was to the label in one country's records — the official status page covers who recognizes which name.