The Marulan sector consists of about half existing alignment and half new alignment around Uringalla. The country is undulating, meaning that significant earthworks and possibly some tunnelling and structures may be required.
This sector involves some difficult terrain, with the Wollondilly River winding between hilly country. The eastern part of the alignment approaching Marulan is unproblematic; curves are minimal and there is even a former trackbed on the north side of the tracks that can be reutilised for most of the length.
