Toronto

This is the best summary I could come up with:

ET on Aug. 14, 2003, Toronto — along with a number of cities including New York, Cleveland and Ottawa — came to a standstill as traffic lights, office buildings, subways and airports shut down.

Tom Adams, an energy analyst, said he recalls the immediate "wild speculation, often political in nature," about the cause of the blackout.

"There was initially speculation that there had been a terrorist attack or that a nuclear power plant had gone up," he told CBC News.

After coming in contact with some overgrown trees, power lines from a FirstEnergy generating plant in a suburb of Cleveland had shut down.

In Canada, the power outage affected most of Ontario including Toronto, Ottawa, Kingston, Sudbury, Kitchener, London and Windsor.

"Other kinds of critical infrastructure — water pumping stations, sewage treatment plants, communication centres — there was a widespread change in the emergency preparedness practices after that event that has given us lasting benefits and, you know, in the ensuing 20 years we haven't had anything like a repeat of that event."

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