The busiest travel days of the year are here — but will it be calm or chaos?

As a procession of semi-trucks rumbled down Yonge Street in Toronto flying Iran’s prerevolution flag and blasting their air horns on Sunday, Rafat Mirlohi looked on with a mix of hope and distress. For four days, she has been unable to reach family in Iran while a crackdown on countrywide anti-government protests has killed at least 500 people, according to reports, and shut down phone and internet contact with the outside world.