Mississauga sits on the western shore of Lake Ontario in the Regional Municipality of Peel, directly west of Toronto. The city covers roughly 288 square kilometres of land and claims about 13 kilometres of lakefront. It’s bordered by Oakville and Milton to the west and southwest, Brampton to the north, Toronto to the east, and Lake Ontario to the south and southeast. A small corner meets Halton Hills in the northwest. With the exception of the Etobicoke Creek corridor on the southeast edge, where the creek marks much of the boundary with Toronto – Mississauga shares land borders with all of these neighbours, which helps explain our tight economic and transportation links across the region.
Landforms and Topography
Stand anywhere in north Mississauga and you’re on ground that gently tilts toward the lake. Elevations fall from close to 190 metres above sea level in the north to about 76 metres at the shoreline—a descent of roughly 110 metres over about 15 kilometres. The drop isn’t dramatic, but you can feel it in the views: the old shoreline of Glacial Lake Iroquois runs near the Dundas Street corridor, and around Dundas and Mavis the ridge is obvious. On clear days, the vantage reveals the sweep of downtown Toronto and Lake Ontario. Outside the natural river valleys, the landscape is broadly rolling. One of the few man-made “hills” is the former Britannia Landfill near Britannia Road and Terry Fox Way, now a visible rise in an otherwise even terrain.
Watersheds and Waterways
Two river systems shape the city’s geography and our daily lives.
Credit River: The Credit is our signature valley – deep, wooded, and ecologically rich. It arcs south through the city and empties into Lake Ontario at Port Credit. The river effectively separates neighbourhoods on the west from the central and eastern parts of Mississauga. Its banks host trails, salmon runs, and beloved viewpoints. Stewardship and flood management fall under the Credit Valley Conservation Authority.
Etobicoke Creek: On the east side, Etobicoke Creek doubles as a municipal boundary with Toronto for much of its length. North of Eglinton it swings through the infield of Toronto Pearson International Airport. The creek has a long memory: Hurricane Hazel’s 1954 flooding changed planning rules here, and building within the floodplain has since been tightly controlled. Etobicoke Creek and its tributaries are overseen by the Toronto and Region Conservation Authority.
A handful of smaller systems round out the picture. Cooksville Creek and Mary Fix Creek drain the central city and flow into the lake east of Hurontario. In the far northwest, minor tributaries connect to the Sixteen Mile Creek watershed; those waters ultimately exit toward the lake in neighbouring Milton and Oakville.
Shoreline and Lake Ontario
Mississauga’s southern edge runs along Lake Ontario, with a mosaic of parks, marinas, wetland pockets, and redeveloped waterfront districts. Port Credit anchors the lakeshore experience, tying together the river mouth, harbour, and waterfront trail network. East through Lakeview, onshore breezes moderate temperatures in summer and keep springs cool; west toward Clarkson, the lake influence makes winter nights noticeably milder than inland. The waterfront is also where past and future meet as remnants of industry share space with habitat restoration and public realm upgrades.
Neighbourhood Fabric and Land Use
The city’s physical form reflects layers of history. Older villages like Port Credit, Streetsville, Clarkson, and Cooksville grew up along the river and rail corridors, and many retain compact main-street grids. Postwar subdivisions spread out from the QEW and Hurontario, followed by the master-planned communities of Erin Mills and Meadowvale in the late 1960s and 1970s. Today’s land use map blends higher-density mixed-use at the City Centre around Square One, employment districts near major highways and the airport, and established residential areas connected by valleys and greenbelts. From Lisgar and Meadowvale Village in the northwest to Lakeview and Mineola by the shore, neighbourhood identities are strongly tied to natural features, especially the Credit corridor.
Transportation Corridors
Mississauga’s geography is inseparable from its transport network. Highways 401, 403, 410, 407, and the QEW form a regional web, with Hurontario (Highway 10) as the north–south spine. GO Transit rail stations at Clarkson, Port Credit, Erindale, Cooksville, Streetsville, Meadowvale, Lisgar, and Malton align with historical settlement and employment nodes. Bus rapid transit and higher-order transit corridors parallel these routes, knitting neighbourhoods to the lake and to Pearson Airport, which occupies a significant footprint on the northeast plateau.
Climate and Microclimates
Mississauga has a humid continental climate, but conditions vary block to block. Lakeshore neighbourhoods from Port Credit through Lakeview often feel cooler on hot summer afternoons thanks to lake breezes, while evenings stay warmer longer into autumn. Clarkson and other southwest areas are typically milder in winter than the north end of the city. When snow arrives with temperatures near freezing, northern districts away from the lake, around the Derry Road corridor frequently to see higher totals than communities by the shore. Summer brings regular thunderstorms; most are garden-variety, but severe wind events do occur. Historic tornado tracks and notable storms have influenced local emergency planning and the design of stormwater systems.
Green Systems and Conservation
Mississauga’s ravines, wetlands, and woodlots are part of a city-wide green infrastructure network. The Credit Valley and Etobicoke Creek systems support migratory fish, urban wildlife, and extensive multi-use trails. Conservation authorities manage floodplains and erosion, while the city invests in stormwater ponds, channel naturalization, and low-impact development to slow and clean runoff before it reaches the lake. As redevelopment reclaims former industrial lands, especially along the waterfront, new parks and habitat corridors are reconnecting people with the shoreline and restoring ecological function.
Elevation, Views, and Vistas
Because the land tilts to the lake, small changes in elevation make a big difference. The Iroquois shoreline ridge near Dundas Street offers long views east to Toronto’s skyline; bridges over the Credit reveal forested valley walls that feel a world away from nearby arterial roads; and in the north, open skies and higher ground give Pearson’s airfield an expansive horizon. These vantage points are part of daily life with commuter glimpses, trail lookouts, and neighbourhood parks that double as scenic overlooks.
A City Shaped by Water and Movement
From the ancient beach of a vanished glacial lake to the living arteries of the Credit and Etobicoke, Mississauga is fundamentally a city shaped by water. The gentle slope toward Lake Ontario, the shelter of our valleys, and the broad plateaus that carry rail lines and highways have guided where people settled, how neighbourhoods grew, and where jobs clustered. It’s a landscape that rewards exploring on foot or by bike—down to the river flats, across the ridge, and out to the lake – revealing how geography continues to frame everyday life in Canada’s seventh-largest city.