Incredible drone footage has captured the intensity of the slip on Parapara Road about 500m north of the Matahiwi Track.
There are fears the massive slip in the Ruapehu District will leave farmers, schoolchildren and freight companies facing major detours well into next year.
Parapara Rd on State Highway 4 between Whanganui and Raetihi has been closed since Wednesday when the huge crack appeared.
GNS Scientists are describing it as a deep-seated rotational slump.
In the past 24 hours, it's taken more road with it along with chunks of farmland falling into a nearby river.
NZTA says it's still assessing the situation but the National Road Carriers Association says truckies are already bracing for detours to be in place for some time while it's fixed.