Surrounded by bush and boats, Briar Jensen enjoys a perfect day trip to Bobbin Head.

Scratch, scratch, scratch. The brush turkey is moving house - a messy business - which wouldn't be a problem in the middle of the bush. It's just that this turkey, at Kalkari, has decided to move its substantial nest mound from one side of the footpath to the other just outside the visitor centre's door. Consequently, as we step outside to walk the Discovery Track, we're showered with leaf litter.

That's what I love about Sydney - it doesn't take much to get down and dirty in the bush and you don't even have to get off the beaten track.

We're en route to Bobbin Head in Ku-ring-gai Chase National Park and have stopped at the Kalkari visitor centre. Our children loved this place when they were little, with its stuffed exhibits of wallabies, quolls and owls. Our son is now 13 and he's more interested in the pickled snake in a jar and the large topographical map of this rugged terrain.

A panoramic lookout over the park helps put the map in perspective. Peering way down into the valley, we can just make out the suspension bridge over Cockle Creek but Bobbin Head is hidden from view.

Bobbin means "place of smoke" in the local Guringai language and refers to the fog that nestles in the ravines in the early morning. There's a great aerial view of this phenomenon in Kalkari's 3-D slide show.

From the visitor centre the road winds down to Bobbin Head at the confluence of Cowan Water and Cockle Creek. We arrive in a few minutes, unlike early park visitors who travelled by horse and buggy. This was a popular place for picnicking and boat hire in the early 1900s and it still evokes a feeling of yesteryear.

Orchard Park has 1930s-era picnic pavilions on lawns dotted with Norfolk pines, palms and other exotic trees. It's like a potted English park, transported into the Australian bush.

The car park was relocated a few years ago, opening up the foreshore, which is a popular spot for littlies learning to ride bikes and scooters, and anglers of all ages - though I don't see any of them pull in a fish. Across the road the park continues on reclaimed land and includes a large, fenced children's playground and plenty of room for older ones to kick a ball. A canoe-launching ramp is used by serious kayakers and a family pottering around in a varnished timber dinghy.

There's no accommodation at Bobbin Head but there are hundreds of day trippers picnicking here, from snuggling couples to large family groups. Smoke swirls from barbecues and the aroma of grilled meat makes me hungry.

There are a couple of cafes offering eat-in or takeaway. One is housed in the historic Bobbin Inn, built in 1937 through an unemployment relief scheme. You can eat under umbrellas on the terrace or inside, adjacent to the National Parks and Wildlife Service shop, which provides free maps and sells books, gifts and souvenirs.

Galley Foods is on the pontoon at Empire Marina, a short walk across the bridge. There's been a boat shed of sorts here since the late 1890s and in the 1960s the Halvorsen family did a roaring trade hiring out its classic timber craft.

The refurbished marina, which recently changed hands, won the 2009 marina of the year (85 berths and over) award, an industry accolade that recognises service, presentation, facilities and environmental practices.

There's plenty of gleaming fibreglass and stainless steel here but you don't need thousands of dollars to get out on the water. Outboard-powered runabouts with cute, blue-canvas canopies can be hired for up to three hours for less than $100.

A series of interpretation boards describes interesting historical snippets, from rum smugglers to visiting whales. There's a lovely old photo of Eccleston Du Faur, the park's founder, taken at exactly the same spot in 1899, while another board features early documentation of Aboriginal engravings, which, when we turn around, are etched into the sandstone behind us.

There are more engravings and axe-grinding grooves in the bush, a short stroll from the end of Gibberagong boardwalk. This wheelchair-friendly boardwalk starts at the suspension bridge and winds through the mangroves.

There's a network of tracks around Bobbin Head and many people walk in from North Turramurra. Others arrive by ferry from Palm Beach, though it stops at Bobbin Head for only an hour, scarcely enough time to order lunch, let alone explore - we see people running back when they hear the ferry's departure whistle.

Personally, I like the loop drive (as do cyclists), taking in the Kalkari visitor centre on the way in and the Sphinx memorial - a sandstone miniature of the Egyptian Sphinx, carved by a returned serviceman in the 1920s - on the way out. It makes for a well-rounded day trip.

FAST FACTS

Getting there

Bobbin Head is 30 kilometres north of Sydney. Access is via the F3 at Mount Colah and Bobbin Head Road at North Turramurra.

Cruising there

Palm Beach and Hawkesbury River Cruises operates a daily ferry that departs Palm Beach at 11am. Phone 0414 466 635 or see sydneysceniccruises.com. For boat hire from Empire Marinas, phone 9457 9011 or see empiremarinas.com.au. See also nationalparks.nsw.gov.au.