which was the last race the horse competed in?
Canadian International Stakes .
Canadian International Stakes
The syndication deal for Secretariat precluded the horse racing past age three. Accordingly, Secretariat's last race was against older horses in the Canadian International Stakes over one and five-eighths miles on the turf at Woodbine Racetrack in Toronto, Ontario, Canada on October 28, 1
how many lengths did secretariat win the belmont stakes 31 lengths. who was "secretariat"? An American Thoroughbred racehorse. who owned this horse? Penny Chenery. how many years did it's career is racing last? From 1972 to 1973.
Kentucky Derby Canadian International Stakes Canadian International Stakes
Secretariat (horse) Secretariat (horse) Secretariat (horse)
Introduction Canadian International Stakes Canadian International Stakes

At age three, Secretariat not only won the Triple Crown, he set speed records in all three races. His time in the Kentucky Derby still stands as the Churchill Downs track record for miles, and his time in the Belmont Stakes stands as the American record for miles on the dirt. His controversial time in the Preakness Stakes was eventually recognized as a stakes record in 2012.  Secretariat's last race was against older horses in the Canadian International Stakes over one and five-eighths miles on the turf at Woodbine Racetrack in Toronto  Accordingly, Secretariat's last race was against older horses in the Canadian International Stakes over one and five-eighths miles on the turf at Woodbine Racetrack in Toronto, Ontario, Canada on October 28, 1973. 
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Secretariat (horse) [SEP] Canadian International Stakes
The syndication deal for Secretariat precluded the horse racing past age three. Accordingly, Secretariat's last race was against older horses in the Canadian International Stakes over one and five-eighths miles on the turf at Woodbine Racetrack in Toronto, Ontario, Canada on October 28, 1973. The race was chosen in part because of long-time ties between E.P. Taylor and the Chenery family, and partly to honor Secretariat's Canadian connections, Laurin and Turcotte. Turcotte missed the race with a five-day suspension: Eddie Maple got the mount. The day of the race was cold, windy and wet, but the Marshall turf course was firm.