A rockslide on the Sea-to-Sky Highway between Whistler and Vancouver destroyed one vehicle early Thursday morning as boulders the size of cars crashed down onto the road.

Officials have said one person is being treated for minor injuries at Lions Gate Hospital in North Vancouver.

The rockslide occurred around 5 a.m. PT near the exit to Strachen Point Road, about halfway between Horseshoe Bay and Lions Bay.

Highway 99 remains open in both directions, but northbound traffic is restricted to one lane only.

In July 2008, a bus narrowly escaped being crushed by a massive rockslide that closed the route for five days further north on the highway at Porteau Cove. That narrow section of the highway has been closed several times by slides, including closures in 1959, 1960, 1969 and 1982.

Further south on the route in February 2007, the highway was closed for a day by a rock slide just north of Horseshoe Bay and in November of 2008 another small slide occurred north of the junction with Marine Drive near the Horseshoe Bay ferry terminal. Nobody was injured in those incidents.

Stablization work continues on the cliff face above the Porteau Cove section of the route, despite a $600 million upgrade of the highway for the 2010 Winter Olympic Games.

But there has been a dramatic drop in the number of crashes on the Sea-to-Sky Highway since the twisting mountain route was upgraded, according to the Ministry of Transportation.