The nearby Bluestone resorts has submitted plans to restore Blackpool Mill in Martletwy, Pembrokeshire.
A public consultation was launched on Monday on the proposal, which includes a milling experience, Victorian tea room and narrow gauge steam railway.
Bluestone said, if approved, it could create 60 jobs and open in spring 2018.
The disused five-storey mill is in a Site of Scientific Interest (SSSI) and a Special Area of Conservation (SAC) and was operational until World War Two.
Bluestone boss William McNamara said: "The mill's heyday would have been the Victorian era, when the industrial revolution marked a shift to powered, specialist machinery.
"Our proposals will celebrate this bygone time, bringing it back to life."
Keith Lewis, deputy leader Pembrokeshire council, said the plans, subject to approval, offered an "exciting tourism prospect".
A Grade II*-listed 19th Century flour mill could be turned into a Victorian-themed attraction.