Cars travel across the Delaware Memorial Bridge as wildfire smoke from Canada causes hazy conditions.
Heavy, acrid wildfire smoke blanketed much of the eastern United States on Saturday, marring preparations for the weekend's highly anticipated World Cup final to be held in an open stadium in New Jersey.
Wildfires burning in Canada have sent noxious smog billowing across the border, with residents in New York, Washington, D.C., and the American Midwest urged to stay indoors because of dangerously poor air quality.
At one point on Saturday, the smoke made New York the most polluted city in the world, followed closely by Toronto and Washington, according to air-quality tracker IQAir.
The marquee World Cup match, pitting Argentina against Spain, will be played Sunday in an open-air stadium across the river from Manhattan, where the skyline was obscured by dense smoke and people wore masks outdoors.
