A historic lighthouse hanging on the edge of a cliff by its "toenails" at Godley Head will be rescued by helicopter today.
Department of Conservation project manager Grant Campbell said the salvage job for the quake-hit beacon would be complicated and had required some creative thinking.
"This beautiful old structure had an extremely lucky escape and was left clinging to the cliff by its 'toenails' after the February and June earthquakes in 2011."
Professional abseilers will remove the copper dome and outer glass housing from the lighthouse base 50 metres down the cliff face below Godley Head, near Christchurch.
A helicopter will then transport the unit to the DOC compound nearby, where it will be stored.
The prism glass, prism housing and light mechanism will be securely crated and also flown there.
The structure and operating mechanisms were historically significant, Campbell said.
"Once safely moved, our aim will be to restore the lantern house on a new concrete base but for the time being it will be kept in safe storage."
After being damaged in the earthquakes, the buildings and tower were gifted to DOC for possible removal.
The original Godley Head lighthouse was built from locally quarried stone and was first lit in April 1865.
Along with the tower, a double stone, slate-roofed, house was built. This housed the head and assistant keepers and their families. The house will stay on site.
Due to its strategic vantage point, Godley Head was taken over in 1951 as a Defence Reserve for military purposes. During World War II, fortifications were built around the lighthouse and a battery of six-inch guns was installed.
As the lighthouse was in the direct line of fire of the guns, the old tower and lighthouse-keepers' cottage were demolished and the lighthouse moved further down the cliff face.
It was automated in 1976.