Part of the main Helston to Penzance road has been closed after large cracks were discovered on the carriageway.
Recent flooding is believed to have caused the cracks to appear and it could be several months before the road is completely reopened.
A 100-metre stretch of the westbound lane of the A394 near Little Antron Farm, around two miles west of Helston, has been shut.
Highways engineers are now investigating the damage to identify how best to repair the road.
Recent flooding is believed to have caused the cracks to appear and it could be several months before the road is completely reopened.
A 100-metre stretch of the westbound lane of the A394 near Little Antron Farm, around two miles west of Helston, has been shut.
Highways engineers are now investigating the damage to identify how best to repair the road.