Ettrema Gorge is one of the great wild places of eastern NSW. Located in the northern Budawangs (about 150km drive from Canberra) and protected by Morton National Park, Ettrema Gorge starts as a tiny stream on a scrubby sandstone plateau just north of Nerriga Road. Ettrema Creek quickly cuts deep into layers of sedimentary rocks to form a gorge up to 400m deep, flanked by unbroken cliffs up to 100m high. This challenging but rewarding weekend trip will explore the upper reaches of the gorge, entering from Bullfrog Creek (a descent of 200m over 3.5km) and exiting via Myall Ridge (a steep scrambling ascent of 400m over less than 1.5km followed by a walk across a scrubby plateau back to the road). Then there is about 8km of the gorge itself, including passage through magnificent Sentry Box Canyon. Highlights of this trip include incredibly rugged gorge scenery, views, waterfalls, deep crystal clear pools and trackless wilderness atmosphere. Most bushwalkers will find this trip reasonably demanding as it requires rock hopping, scrambling and some wading. You also need to be comfortable with heights as some of the scrambles are exposed. Nonetheless, the pace will be slow, the distances are short and, provided we start walking in good time each morning, there will be plenty of opportunity for swimming. This walk is suitable for experienced bushwalkers. Maps: Touga and Nerriga 1:25,000 topographic.