To tell the truth, I lied. When The Coastal Track people sent information about their three-day hike through Sydney's Royal National Park there was a section asking about my fitness.
I exaggerated enormously and said I exercised once a week.
But on the first day when I queried Colin, our guide, about the route, he pointed to his map and said, "There's the killer bit, 3km uphill on soft sand".
My lie would soon be discovered... to my shame... but the killer bit wasn't that bad.
The Coastal Track is the project of Samantha Madsen, and our walk was along the dramatic coastline an hour south of Sydney, taking in wild beaches, rolling Banksia heaths, waterfalls and rock pools, deep coves and dense bush. At day's end we had a massage then enjoyed glasses of wine and fine dining at our campsite above Wattamolla Beach.
The 26km route - for a cheerful group of six, plus Colin, average age early 50s - started at the small community of Bundeena and made a brief digression around Port Hacking Point to see Aboriginal rock art attributed to the Dharawal people.
Here were images of a stingray, a totemic male figure, a kangaroo and a whale carved more than 200 years ago. But no one knows how much more.
Then we headed into the 15,080ha Royal National Park, dedicated in 1879 and the second oldest national park in the world after Yellowstone.
This is an extraordinary landscape: the Hawkesbury sandstone around the Woronora Plateau is estimated at 200 million years old and throws up unusual colours, oddly coloured banding (Liesegang rings) and weirdly alien rock formations sculpted by wind and water.
After Colin's "killer bit" we're on the hard shoulder of Australia and can see massive cracks in the rock ready to break off in strangely symmetrical blocks. Come back in a few thousand years and some of this won't be here.
On the final day Colin says to me, "You're the only writer I've met who takes photographs."
But how can you not? Cheese-coloured stone, rock formations like frozen whirlpools, massive fingers of sandstone pointing out above the ocean like surreal shapes from Mordor, honeycomb patterns in rusty rocks, stone like warped stalactites, a clifftop lake acting as an infinity pool to the sea beyond, a dam built when people lived out here in the Depression...
At Wattamolla I take a cliched photograph of solitary footprints along the empty sand.
"They had to close the park on Boxing Day," says Colin that night.
"There were 22,000 people on the beach."
We've come at a better time.
Above the beach is the camp where we enjoy our private tents and fine dining.
Award-winning chef Rob Lisk of R'n'R Catering and his crew set up the dining table under a large tent.
We settle down for drinks, king prawns, superb lamb...
From his tiny, lamp-lit tent Lisk creates culinary magic - and desserts we take photographs of. A bleary-eyed hour before sunrise the following day I hear incessant laughter again. I'm not used to the dawn chorus of Australian birds. Over breakfast I tell my new-found friends I once mistook the avian racket for car alarms.
And this park boasts considerable bird life. Colin points out the New Holland honeyeater, yellow-tailed black cockatoos down from the Blue Mountains to escape the winter chill, sea eagles, wattlebirds, rosellas, kookaburras...
The park is also home to wallabies, a few varieties of snake, beautiful dragon lizards with geometric patterning and innumerable deer, the descendants of those released here more than a century ago to give the English colonists some sport.
The second night, as we eat fresh scallops and delicious duck under the stars, a fox trots through the camp. Then a possum blinks into the light.
It had been quite a day until then: we'd walked across a clifftop 200m above the turbulent ocean, swum in a secluded lagoon and splashed under its waterfall, seen where a hermit had lived 30 years ago on a site of an ancient Aboriginal midden, taken photographs of distinctive Eagle Rock then made the steep descent to Garie Beach where surfers braved towering waves while we slumped in the sand.
On the final afternoon as we lie on the grass at Otford, happily weary, I ask Chris what he would tell his friends. Like me, he'd felt slightly embarrassed about the luxury treatment Madsen and her crew afforded guests, "but the walk was more of a test than I'd thought".
I felt the same: not too arduous but a rewarding workout. Sort of boot camp for lazy people - with fine food, wonderful wine, and good company in a very special place.
Further information: The Coastal Track offers two- and three-day catered and guided package tours which include seasonal highlights such as whale migration (May), flowers in bloom (September) and a spring weekend (November). There are also tailored walks for photographers, singles, over-50s and women-only groups. For details of the track, accommodation and catering see thecoasttrack.com. To check out Rob Lisk of R'n'R Catering visit randrcatering.com.au.
Graham Reid travelled to Sydney courtesy of Tourism Australia and was hosted by The Coastal Track.