Colo River is formed by the confluence of the Wolgan River and the Capertee River north of Lithgow. It flows eastwards through a deep gorge in the Wollemi National Park. Wollangambe River and Wollemi Creek are the other main feeder streams.
The river is known mostly as a summer bass fishery, although eels, Macquarie Perch (totally protected), eel tailed catfish, a few trout and some estuary species are present.
The Colo sits mostly in rugged country with no road access, although its lower reaches are accessible by vehicle off the Putty Road. The river descends 214 metres over its 86 kilometres course.
Walking access via Bob Turner Track, Canoe Creek and Wollemi Creek is best suited to experienced bushwalkers. There is no mobile phone reception.
The best bass fishing is typically at dusk and dawn or immediately following heavy rain or during minor flooding (never enter flood waters).
Bass fishing with surface lures, spinner baits and hard body lures is popular with spin anglers.
Fly fishing with large dry flies such as surface poppers, grass hoppers and christmas beetles is very popular particularly at dusk and following heavy rain. Streamers and nymphs are preferred during the middle of the day when the fish are less active near the surface.