Markham covers 212.47 km² (82.04 sq mi), making it one of the largest and most dynamic municipalities in York Region. The city’s centre sits near 43°53′N 79°15′W, with borders that connect it to five neighbouring municipalities. To the west, Markham meets Vaughan along Yonge Street and Richmond Hill along Highway 7 and Highway 404. Its southern edge runs along Steeles Avenue, directly touching Toronto. To the north lies Whitchurch-Stouffville, while the eastern boundary follows the York-Durham Line, where Markham meets Pickering. This positioning makes the city both suburban and metropolitan, offering quick access to Toronto while maintaining its own distinct identity.
Topography
Markham rises gently across the landscape, with an average elevation of 200 m (660 ft). The area is marked by softly rolling hills, giving its neighbourhoods a sense of openness and variation in terrain. Two rivers, the Don River and the Rouge River, run through the city, shaping its parks and natural spaces. Tributaries branch across residential and commercial areas, often forming scenic trails and conservation spots. To the north, the Oak Ridges Moraine contributes to higher elevations and plays an important ecological role, acting as a vital watershed for southern Ontario. This natural backdrop creates a blend of urban life with preserved green corridors.
Climate
Markham shares a climate with Toronto but tends to be slightly cooler, on average 1-2 °C (1.8-3.6 °F) lower than downtown Toronto. Classified as humid continental (Dfb, Köppen), the city experiences warm and humid summers followed by cold, snowy winters.
Summers (May to October) bring steady rainfall, with temperatures often in the mid-20s °C.
Winters are marked by frequent snowfall, averaging 146 cm annually, and temperatures that regularly fall below freezing.
Extreme records include a sweltering 37.8 °C (100.0 °F) during the 2001 heat wave and a chilling -35.2 °C (-31.4 °F) in the 1994 cold snap.
The Buttonville Airport, located within Markham, provides long-term climate records that highlight the city’s varied conditions. With over 862 mm of precipitation annually, residents experience all four seasons in full, from bright fall foliage to crisp spring thaws.