The best one day walk in the blue mountains. steep in parts.
Walking trails, including:
the Wentworth Pass track
Which allows you to swim at the bottom of the falls.
Darwin's Walk
Named after charles darwin who visited the area, and did the walk. about 2 hours long, staring from the station and ending at the falls, so great for those visiting by train. gentle grade.
Canyoning and abseiling are also popular activities.