The "Blue Mountains Range" comprises a range of mountains, plateau escarpments extending off the Great Dividing Range about northwest of Wolgan Gap in a generally southeasterly direction for about , terminating at . For about two-thirds of its length it is traversed by the Great Western Highway and the Main Western railway line. Several established towns are situated on its heights, including Katoomba, Blackheath, , and . The range forms the watershed between Coxs River to the south and the Grose and Wolgan rivers to the north. The range contains the Explorer Range and the Bell Range.