<P> The Three Sisters are an unusual rock formation in the Blue Mountains of New South Wales, Australia, on the north escarpment of the Jamison Valley . They are close to the town of Katoomba and are one of the Blue Mountains' best known sites, towering above the Jamison Valley . Their names are Meehni (922 m), Wimlah (918 m), and Gunnedoo (906 m). </P> <P> The Sisters were formed by land erosion . The sandstone of the Blue Mountains was eroded over time by wind, rain and rivers, causing the cliffs surrounding the Jamison Valley to be slowly broken up . </P>

What are the three sisters in the blue mountains