Several wildfires in the Canadian Rockies’ largest national park sent up to 25,000 visitors and residents fleeing west over the last open mountain road on Tuesday, navigating through darkness and soot after a government alert during the area’s busiest tourist time of the year.

“It’s wall-to-wall traffic,” Carolyn Campbell, an Edmonton resident, said by phone from her vehicle.

“(The smoke) is pretty thick. We’ve got masks in the car.”

She said it took hours to move about four miles, and worried about others who fled with little petrol in their tanks.

Hundreds of wildfires are burning in western Canada, and those fleeing Jasper National Park and Jasper town, home to 4,700 residents, in Alberta province were given the unusual order on Tuesday to make a vast U-turn east if they needed a place to stay.

To the west, British Columbia province already had more than 300 wildfires of its own.

Stephen Lacroix of the Alberta Emergency Management Agency said Jasper town estimated about 10,000 people, including seasonal workers, were there when the evacuation call went out.

Mr Lacroix said police were going door to door to make sure everyone has left. He also said Parks Canada estimated about 15,000 people had been in the park.

Photos and videos shared on social media overnight into Tuesday showed bumper-to-bumper vehicles, their headlights glowing, inching through swirling tendrils of smoke.

Fires threatening from the northeast cut off road access east to Alberta’s capital, Edmonton.

Another fire roaring up from the south forced the closure of the north-south Icefields Parkway. That left one route open west to British Columbia.

But Alberta fire officials said British Columbia had its hands full with its own evacuations.

Alberta public safety minister Mike Ellis said reception centres were instead being set up in Grande Prairie and Calgary, Alberta, requiring massive detours through parts of British Columbia by the drivers fleeing the Jasper area.

Alberta has been baking under scorching temperatures that have forced another 7,500 people out of a string of remote communities. About 170 wildfires were burning across the province.

Jasper council and Jasper National Park said the evacuation was “progressing well” and park and town officials scrambled to clear traffic gridlock, find fuel for vehicles and help vulnerable people to safety while marshalling resources to battle the fires.

“Everyone in Jasper must evacuate now,” the Alberta government said in an emergency alert on Monday. Parks Canada noted “an evolving and dynamic situation”.

Evacuees were told they had five hours to clear out, by 3am on Tuesday, and carry with them key documents, pets, medication and any other emergency supplies.

A record number of wildfires in 2023 forced more than 235,000 people across Canada to evacuate and sent thick smoke into parts of the US, leading to hazy skies and health advisories in several US cities.