A WOMAN has been airlifted to Royal Perth Hospital this afternoon following a serious crash on Forrest Highway.
The single vehicle accident happened just before noon in the north-bound lanes of the highway about 500 metres past the Old Bunbury Road turn off.
Police said the woman, believed to be in her 50s, has sustained serious injuries.
It is not yet clear how her 4WD came to leave the road.
It appears to have rolled several times and come to rest in a ditch about 10 metres from the highway.
The woman was travelling alone.
Traffic was delayed but is now moving as normal.
Police remain at the scene.
Enquiries are continuing.