 The challenge of moving freight across the rugged Blue Mountains and through the demanding Zig Zags from Eskbank to Penrith led local engineers into a worldwide search for steam engineering solutions, which were tested between Sydney and Eskbank.The results of the trials were then translated into purchasing and design decisions which led to the creation of Australian locomotives which were an amalgam of British and American design and construction principles.The place possesses uncommon, rare or endangered aspects of the cultural or natural history of New South Wales.