Marathons Found In Ontario
View all ↓Marathons in Ontario 2025 - 2026
The most comprehensive list of Marathons in and near Ontario in 2025 - 2026. Find your perfect race!
Ontario's marathon landscape spans urban waterfront courses, rural countryside routes, and challenging Canadian Shield terrain. The full 42.2-kilometre distance showcases the province's diverse geography, from Toronto's lakefront to Ottawa's canal pathways and the rolling hills of wine country. The primary marathon season runs from April through November, with the largest events in spring and fall.
The province's signature marathon events reflect Ontario's varied environments. Toronto's waterfront routes offer predominantly flat courses ideal for Boston qualifying attempts, while Niagara's events incorporate dramatic escarpment views. Ottawa's canal system creates natural race corridors, and Muskoka's challenging routes wind through Shield country with significant elevation changes.
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Race Calendar: Marathons Found In Ontario