Five people have been hurt in a serious crash just north of Lions Bay.

Fire Chief Andrew Oliver says the collision closed the Sea-to-Sky in both directions.

"They had a head-on just outside Brunswick Beach about a kilometre past Lions Bay, north.  And a big truck with a van hit a little Ford Explorer, spun it around and pushed it into the rock face."

Two people had to be extracted from the SUV.

It's not believed any of the injuries are life threatening.