State Highway 2 through the Karangahake Gorge will be closed between 8pm and 5am on Monday, February 10, and Tuesday, February 11, for slip repair works east of Karangahake Village.
Stop/Go traffic management will be in place between School Road, Karangahake Village and Waitawheta Road, Waikino overnight for further workson the slip repair site on Wednesday 12 and Thursday, February 13.
Signage and cordons will be in place between Paeroa and Waihi.
NZTA's acting Waikato Transport System Manager Rob Campbell says detours for this route are significant and encourages motorists to plan their travel for outside closure times, where possible.
"The southbound detour takes motorists south on SH2 from Waihi to Tauranga, then onto State Highway 29 over the Kaimai Range, State Highway 24 to Matamata, State Highway 27 to Tatuanui and State Highway 26 to Paeroa. Motorists travelling from Paeroa take the same route, in the opposite direction.
"Northbound, motorists travelling from Waihi should take State Highway 25, turning onto State Highway 25A (Kopu-Hikuai Road) and then State Highway 26 between Kopu and Paeroa, with motorists travelling from Paeroa taking the same route, in reverse."
Karangahake Gorge is likely to be closed for a further two nights later in February for road resurfacing.
These works form part of the Transport Agency's largest maintenance programme for the past decade.