The Illawarra Fly is the height of rainforest fun and nearby Robertson has just the B&B to complete a Southern Highlands short break, writes Vanessa Walker.

The Southern Highlands town of Robertson in NSW always feels a little eerie — it's saturated with gorgeous countryside but is often devoid of people. Perhaps it's the comparison with the seaside settlement of Jervis Bay where we set off from, but as we climb the winding roads of the mountains, shedding the sun and warmth as we go, I feel like we're heading into the unknown. It doesn't help that when we eventually pull up at the town, we are greeted with a pizza joint named Pizzas in the Mist.

What better way to shake off this feeling and get a fix for where we are than to rise above it all — and go on the Illawarra Fly, a treetop walk suspended 25 metres above the rainforest floor, with a view over the Shoalhaven to the Pacific Ocean.

But first we must satisfy our children's curiosity and stay a night at a B&B intriguingly named The Castle. In order to have one more day of holiday, I've talked up this place to my three-year-old daughter and six-year-old son and I fully expect to have to answer for my sins when we pull up at a place that's clearly a faux — in their parlance a "stink" — castle.

You can imagine my joy when the vast wrought-iron gates slowly swing open and our car tyres crunch over the gravel driveway as we drive into view of a castle… almost. OK it's red brick rather than stone (a small detail the kids miss) but it's shaped like a castle, it has a turret and a slate roof, lancet leadlight windows and a garden that is littered with griffins and gargoyles, even a pond filled with koi.

As the black double doors open and we're greeted by the owners, Graeme and Ken, the first thing my son lays his eyes upon is a medieval sword and shield leaning by the door, then a dining room laid out for a formal dinner with shining silver, crystal goblets and fine china, as though set for kings and queens.

My eyes fall despairingly on the way that every surface is covered with a display of precious ornaments and objects that look very expensive and very breakable then I look down to the plush soft carpet and pray we don't somehow stain it. The kids chase after Tiger, the cat who dislikes children — more cause for concern!

The Castle is really quite amazing, from the 3.6metre-long glazed-terracotta fireplace surround (made by Melbourne sculptor Graeme Foote, the only other one in the world is in New Zealand's parliament house) in the sitting room to the way every single interior aspect has been enhanced: from the gold and cornflower-blue cornices and ceiling roses and flowery light fittings, to the claw-foot bath, brass light switches and ornate carved furniture. The attention to detail is phenomenal: I'm told the Australian-cedar circular staircase that leads up to our room was made in Melbourne to resemble those in Irish castles, and then shipped to Robertson in pieces, taking three carpenters and three apprentices three days to piece together.

As we sit down to an afternoon tea of lemon jelly cake, made by Graeme, it emerges that Graeme and Ken build the entire place themselves, some twenty years ago, on weekend visits from Sydney. We stay in the west bedroom in the quietest atmosphere we have experienced in years and awake to a breakfast of coddled eggs, roasted tomatoes, real coffee and Graeme's homemade quince paste and kiwifruit jam with sourdough bread. The kids play outside (phew — although I'm slightly concerned to learn The Castle is opening up their exquisite garden for the Open Garden Scheme that very day) while Graeme cranks up an old gramophone they've restored and we are treated to a Julie Rogers album.

Ken and Graeme are gentle hosts who deal with their inappropriate guests graciously, waving us off as we head to the Fly, the real reason for our visit to the Highlands.

First opened in 2008 it is the only tree top walk of its kind in NSW. We start at the modern visitor centre then stroll on a path through the rainforest. Every 20 metres or so there's a sign detailing what kind of flora we're looking at and explaining the type of fauna that resides in the forest, including wombats, echidnas, wallabies, kangaroos, lyrebirds, rosellas and kookaburras.

To our excitement the path leads to the steel walkway that marks the beginning of the 472-metre-long treetop walk part and it's a few minutes into this that I remember my slight but definitely-still-there fear of heights. It's sensational to pass through the trees, first at eye level then eventually looking down onto the vines and creepers then the shorter varieties such as native mulberry and musk daisy bush and finally being among the branches of huge eucalypts and blackwoods. But when my children make the cantilevered part of the Fly bounce a little I almost freak out.

My daughter insists on pointing through the steel floor to the forest waaaay below and my husband keeps taking 'happy snaps'. In the few moments of clarity I do have, I realise it's sensational. It's utterly quiet and the view is expansive, taking in the mountains, farming land, bushland and the sea. We walk up the stairs of the Knights Tower, at 45 metres above the forest floor the highest point of the walk and above all of the surrounding trees. It's a once in a lifetime feeling that I pause for briefly before I scramble down the spiral stairs (evidently rather fast, my thighs ache the next two days).

The walk back is meandering and pleasant and we enjoy a lovely lunch at the visitor centre. I'm thankful for their thoughtful café-style menu, which doesn't force us into hot chips through lack of choice and the information displays about the rainforest that so enchants the kids, so I can have a calming cup of tea. A lovely journey all round especially now I'm on solid ground.

The Castle, The Old Road, Robertson. $230 per couple per night (excluding dinner).

Illawarra Fly, 182 Knights Hill Road, Knights Hill, NSW. Adults $24, children (6-16) $10, five and under free.

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