Hat Hill Canyon is a good canyon in Hat Hill Creek, north of Blackheath. It has been known for many years. Up until mid 2008 the Blackheath Sewage Treatment Plant was releasing treated effluent into the creek, so the canyon was not often done. The closure of the plant should increase the water quality in the creek.
Hat Hill Canyon consists of three distinct sections, separated by pleasant creek walking. No abseils are required, though there are a few short swims.
Turn off the Great Western Highway on to Hat Hill Rd at Blackheath. Drive along Hat Hill Road to where it turns sharply right after 3.1km, and after a further 500m, turn left in to Godson Ave (unsealed), just next to Mt Booralee. Turn right at the intersection at MGA509774 and park in the first pull in bay on the left.
About 10m past this, walk down a fire trail on the left. Ignore a foot track to the left at a cairn after 150m - this leads to the climbing area of Atlantis in the upper part of the creek. Continue down the fire trail until it peters out at a burnt out car, and then keep walking down the ridge and into the creek at the creek junction.
Follow the creek down to where the first section of canyon starts at the next creek junction at MGA512783.
The first section of canyon is impressive, but short, ending shortly after the junction with the next side creek on the right. There is a short swim and some wading. The side creek also has a short section of canyon.
The second section of canyon begins around MGA513786. There is a short, awkward drop into a deep dark section with some swimming. The canyon section ends a little way before the major tributary on the left. This tributary has some canyon in it as well.
The third and most impressive section begins at around MGA513795 and continues intermittently to where the creek opens out at MGA513801. There is some wading to about waist deep. The major side tributary on the right has a double arch in the rock at the waterfall, and is well worth a look.
It is well worth continuing down the creek for another 200m to the impressive Hat Hill Falls, where the creek tumbles into the valley below.
To exit, retrace your steps back through the lower section of canyon, and exit up either the gully to the north at MGA514795, or to the south east at the creek junction at MGA513793. Walk up to Bald Head Ridge and back along the track that goes over Hat Hill to the road. It is about 1.5km back along roads to your car.
It is also possible to abseil Hat Hill Falls and descend to the Grose. However, this would make the trip into a longish day for little extra gain. There is also a little known tricky pass, Lews Pass, which bypasses Hat Hill Falls on the left.