Canadian Tire Motorsport Park: Canada's Fast and Fearless Original
Drive an hour or so east of Toronto, past Bowmanville and into the rolling farmland of Clarington, Ontario, and you arrive at one of the great natural-terrain road courses of North America. Canadian Tire Motorsport Park - known to generations of racing fans simply as Mosport - is a circuit of just under four kilometres and ten corners, draped across a ridge of hills so that almost no part of the lap is flat. It is fast, it is undulating, and it has been frightening and delighting drivers in roughly equal measure since it opened in 1961.
From farmland to Mosport
The circuit was born in the late 1950s, when Canadian racing enthusiasts went looking for a permanent home for the sport. The land they found northeast of Bowmanville offered exactly what designers of that era prized: natural elevation, long sightlines and terrain that would let the track flow with the landscape rather than fight it. The name they chose was a simple contraction of the words motor and sport - Mosport - and it stuck so firmly that many fans still use it today, more than a decade after the official renaming.
When the track opened in June 1961, it announced itself with real star power. Stirling Moss, then at the height of his fame, won the headline sports car race that first season, and the circuit honoured him by attaching his name to its slowest and most technical section. Moss Corner, the double-apex hairpin at turn five, remains one of the most recognisable corner names in Canadian motorsport. From the very beginning, Mosport was not a regional club track; it was a venue with international ambitions.
The lap: ten corners and nowhere to rest
What makes the circuit special is the way speed and gradient combine. The lap begins with a plunge into turn one, a fast right-hander taken while the car is still settling, and then drops steeply into turn two, a long downhill left that is widely regarded as one of the most demanding corners on the continent. The road falls away from the driver mid-corner, the exit is blind, and commitment has to be total. Drivers who race there consistently name it among the great corners of world motorsport.
From there the track climbs and dives through quick linked corners to Moss Corner, the one genuine slow point on the lap, where the double apex punishes greed on entry. Then comes the long run back: a sequence of sweeping, uphill right-handers taken at enormous speed, feeding onto the back straight - named in honour of Mario Andretti - before the final corner spits cars back onto the pit straight. There is no chicane-and-hairpin rhythm here, no artificial slowing. The average speed is among the highest of any road course in North America, and the elevation change means the car is almost never on an even keel. Set-up compromises that would be invisible elsewhere are exposed ruthlessly.
Formula One's Canadian home
Between 1967 and 1977, Mosport hosted the Canadian Grand Prix eight times, sharing the race in its early years with Mont-Tremblant in Quebec before becoming its regular home. The roll call of winners reads like a history of the era: Jack Brabham took the first Grand Prix there in 1967 in treacherous wet conditions, Jacky Ickx won in 1969, and Jackie Stewart mastered the place twice, in 1971 and 1972.
The 1973 race, won by Peter Revson, earned a curious place in the sport's history books: amid rain, chaos and confusion over lap counting, it saw the first ever deployment of a safety car in a Formula One World Championship race. Emerson Fittipaldi won in 1974, James Hunt in 1976 during his championship-winning season, and Jody Scheckter took the final Grand Prix at the track in 1977, driving for the Canadian-owned Walter Wolf Racing team - a fittingly patriotic footnote.
By then, however, the writing was on the wall. Formula One cars had become dramatically faster than the circuit's barriers, run-off areas and facilities could safely accommodate, and from 1978 the Canadian Grand Prix moved permanently to the new circuit on Île Notre-Dame in Montreal. Mosport's Grand Prix era was over, but its character - the very speed and danger that ended its F1 tenure - was preserved.
Can-Am thunder and two-wheeled history
If Formula One gave Mosport prestige, the Canadian-American Challenge Cup gave it noise. The circuit was part of the legendary Can-Am series from its inaugural 1966 season, and the spectacle of essentially unlimited sports prototypes cresting its blind rises became one of the defining images of the track. The great names of that era - McLaren, Hulme, Revson, Donohue and their rivals - all raced there, and the combination of huge horsepower and plunging terrain suited the series perfectly.
The track also carved out a place in motorcycle history, hosting a round of the world championship in 1967, and it became a fixture for Canadian national racing on both two wheels and four. Trans-Am, Formula 5000, IndyCar and endurance sports car racing all visited over the decades, giving Mosport one of the most varied competition histories of any circuit in the Americas.
Decline, rescue and a new name
Like many classic circuits, Mosport endured lean decades in which maintenance lagged and its future looked uncertain. The turning point came in 2011, when an ownership group that included Canadian racing hero Ron Fellows and businessman Carlo Fidani purchased the facility. Investment followed on a scale the old place had never seen: repaved surfaces, a modern paddock, new garages, an event centre and upgraded spectator areas.
In 2012 a long-term partnership with the Canadian Tire retail chain gave the venue its current name, Canadian Tire Motorsport Park. Purists grumbled, as purists do, but the essential point was preserved in full: the layout of the Grand Prix circuit was not neutered. The fearsome downhill of turn two, the flat-out sweeps, the blind crests - all of it survived the renovation intact.
Race weekends today
The modern calendar is deep and varied. The IMSA WeatherTech SportsCar Championship brings top-level prototype and GT racing to the circuit each summer, continuing an endurance racing tradition that stretches back to the track's earliest years. The NASCAR Truck Series raced there from 2013, and its debut visit produced a last-corner collision-and-pass finish that instantly became one of the most replayed moments in the series' history. Canadian Superbike, national sports car and touring car series, and a beloved vintage racing festival round out a season that runs from spring to autumn.
Beyond the Grand Prix circuit itself, the property includes a separate driver development track and a karting facility, making it a genuine campus for Canadian motorsport rather than a single ribbon of asphalt. Champions have learned their craft there; club racers spend whole summers there; and fans camp on the hillsides much as they did in the Can-Am days.
Why it still matters
In an age of stadium-section street circuits and manicured run-off, Canadian Tire Motorsport Park is a living argument for the older idea of what a racetrack should be: a road laid over real landscape, where gradient and camber do the work that chicanes do elsewhere. It rewards bravery and precision simultaneously, punishes hesitation, and gives spectators sightlines - down into turn two, across the valley at Moss Corner - that modern venues simply cannot match. Few circuits anywhere combine this much history with a layout so nearly unchanged from the day it opened.
Explore on the map
Canadian Tire Motorsport Park sits in the countryside of Clarington, Ontario, within easy reach of Toronto and the busy motorsport corridor of the Great Lakes region. You can find its exact location, along with hundreds of other circuits, speedways and racing venues across Canada and the rest of the world, on our interactive map. Zoom in on southern Ontario and you will see just how rich the racing landscape around the old Mosport really is.