The smallest Great Lake by area but deep, the final step before the St. Lawrence to the sea.
Surface area
18,960 km²
Maximum depth
about 244 m
Elevation
75 m
Continent
North America
Countries
United States & Canada
Did you know?
Though smallest in area, Lake Ontario holds far more water than Erie because it is so much deeper.
Little-known fact
It sits at the foot of Niagara Falls, catching all the water that pours over from Lake Erie above.
Highlights
- Smallest Great Lake by area
- Deeper than it looks
- Lies below Niagara Falls
Life in the Lake Ontario
The fish and animals, waterbirds and water plants — including some of the rarest — that this water supports.
Animals & fish
Atlantic salmon
The “king of fish” — it is born in a river, grows at sea, then fights its way back upstream to spawn where it hatched.
Common snapping turtle
An armoured, prehistoric-looking turtle with a powerful beak that haunts the muddy beds of North American waters.
Waterbirds
Mallard
The familiar green-headed dabbling duck — ancestor of most domestic ducks — found on waters worldwide.
Water plants & reeds
Cattail (bulrush)
The brown sausage-headed reed of marshy shallows, edible from root to pollen.
Interactive · 3D dive
How deep does a lake go?
A lake is layered from the sunlit, weed-filled shallows down to a cold, dark bed. Tap a zone to dive the submersible through the water column — and meet the life that belongs at each depth.
Tip: hover the column to tilt it · tap a layer to dive
Littoral Zone
The warm, bright band close to shore where sunlight reaches the bottom. Reeds, water lilies and rooted plants grow thickly here, making it the busiest, most crowded part of the whole lake.
Who lives here