Sixty or so years after Captain Cook passed by, the forests of North Brother Mountain and good access to waterways for easy transport and shipping, meant that timber harvesting contributed to the establishment of the Camden Haven area, and pioneer settlements developed around them.

Popular for almost 30 years as a hang-gliding site, most park visitors leave launching themselves off the summit to the professionals, and just enjoy watching the awesome spectacle as experienced pilots lift off from and soar around the lookout area.

The local Aboriginal people tell a Dreamtime story of three brothers in the Birpai tribe who were killed and buried where the mountains stand. The youngest of the three brothers was Dooragan, hence the park's name. Coincidentally, 'Three Brothers' was also a name given to the three mountains by Captain James Cook as he sailed past in 1770, without any knowledge that the local Aboriginal people referred to them in such a similar way.

While most visitors may see certain species around the lookouts - like cheeky magpies, currawongs and kookaburras - those with an ear for birds will find the forest has a greater diversity than their eyes would have them believe. Occasionally, a lucky birdwatcher may spot the dramatic flash of rainbow colour as a wompoo fruit-dove darts from place to place in search of rainforest fruits. Overhead, resident wedge-tailed eagles demonstrate their clever use of up-drafts, watching for where their next meal might come from.