A 200km stretch of the Main Trunk Line railway, including Taumarunui and the Raurimu Spiral, is set for recognition by the Historic Places Trust.
The proposed historic area was a microcosm for New Zealand's rail history and home to key 20th century engineering developments, trust researcher Karen Astwood said.
"The Mangaturuturu Viaduct is the highest altitude railway structure in New Zealand while the Raurimu Spiral is well-known in world terms for its design ingenuity," Ms Astwood said.
"Of course, the tragedy of the Tangiwai disaster, with the memorial on the banks of the Whangaehu River, is also a reminder of the forces of nature."
The historic area would stretch from the Taumarunui railway station south to the Makohine Viaduct near Ohingaiti.
Work on the Main Trunk began at Te Awamutu in 1885, and it remains one of New Zealand's biggest infrastructure works.
Sites within the proposed historic area have already been placed on the trust's national register, including the Raurimu Spiral, five viaducts and the Ohakune railway station.
