 The line had reached Bowenfels by 1869 and the section to Wallerawang opened on 1 March 1870.To complete this stage, major crossings were required, of Farmers Creek via the Bowenfels rail viaduct, completed in 1870 and replaced in 1921; Marrangaroo Creek (also known as Middle River) via the Marrangaroo railway viaduct; and the Coxs River via a single-track stone railway bridge at Wallerawang, completed in 1870.The builder, George McGarvie Donald of Lithgow, was a master stonemason and builder who helped create the city of Lithgow.