Four giant timber viaducts built in Southland nearly a century ago have been saved in a collaborative funding deal.
The four viaducts were built in the rugged Waitutu Forest on the south coast of the Fiordland National Park in the early 1920s as part of a timber tramline to the Port Craig logging and sawmill operation.
The sawmills were dismantled after the Great Depression and in the 1990s the viaducts became part of the Hump Ridge Track.
The largest viaduct, the Percy Burn - the highest timber trestle bridge in the Southern Hemisphere - had to be closed in May last year because of safety concerns with the decay and corrosion of the key structural elements.
The four viaducts have Category 1 Historic Places Trust registration and are listed as one of New Zealand's top 50 engineering structures.