The area has been turned into mountain bike manna by the Glenrock Trail Alliance group (mainly NPWS and the the Hunter Mountain Bike Association) with dedicated bike trails that will test your skills and endurance.
The alliance's aim is to 'see a sustainable and enjoyable network of single trail not only legalised, but also maintained in a sustainable manner, within the park' (GTA, 2013).
They have certainly succeeded; the northern end of the park is now a networked series of trails, from fire-trail to twisting single track, with berms, drops, rocks and jumps to satisfy the craziest downhill racers, while offering a safe and sedate track through for the less fearless.
The most popular loop takes around an hour of non-stop riding, but you'll want to allow time to stop and enjoy the brilliant views of the ocean, and interesting features along the way, like Leichhardt's Lookout, with its fascinating display covering the indigenous, white exploration and early mining history of the park.
The area is named after Glenrock Lagoon, seen here from Leichhardt's Lookout