Washington, Sep 18 (IANS): The Yosemite National Park, one of the most visited in the US, on has closed to all visitors and vehicular access due to significant smoke impact from the raging wildfires in the West Coast and hazardous air quality.

All park entrance stations and roads were closed from 5 p.m. on Thursday, officials said in a statement.

With air quality projected to be in the unhealthy to hazardous range over the next several days, the park anticipates the closure will be in effect until at least throughout the weekend, reports Xinhua news agency.

"The park will continue to assess the smoke impacts, air quality index, and fire activity throughout the region," the statement said.

The park will reopen when it is again safe for visitors and employees to return to the park.

Yosemite National Park's closure is in alignment with the closure of Sequoia and Kings Canyon National Parks and the surrounding national forests, according to the statement.

Designated as a World Heritage Site in 1984, Yosemite is internationally recognized for its landscapes and biological diversity, receiving some 4 million visitors each year.