Tread Lightly Eco Tours. This eco-minded company operates small-group tours of Blue Mountains National Park and guided day and night walks, as well as four-wheel-drive tours and breakfast trips to view wildlife. Half- and full-day walking tours take in such areas as Fern Bower, Blue Gum Forest, and the Ruined Castle. 102 Great Western Hwy., Medlow Bath, New South Wales, 2780. 04/1497--6752; www.treadlightly.com.au. From A$65 .