Somewhere around 2,500ft, the whole muddy process really begins to hurt. I halt again, crouch over, drop my hands to my knees, and try to inhale desperate lungfuls of the soupy tropical air. Looking down, I notice that almost every part of my clothing is now smeared with dirt. I attempt to go on, but the lactic acid in my calves will no longer be silenced by a meagre minute's respite. Once more, I let out a muttered curse. I do not consider myself unfit. But hiking to the summit of Nevis Peak – the 3,232ft volcano that dominates the Caribbean island of Nevis – is proving quite the challenge.
I cast my mind back two hours: an early start at Rawlins Village in warm morning light, walking past the ruins of an 18th-century windmill, its tumbled brickwork mired in undergrowth; the gentle curve of the initial stages of the trail, the narrow path winding between papaya and mango trees. And then the hard surge in gradient, the canopy closing overhead, the atmosphere thickening, the oxygen thinning, sweat cascading into my eyes.
The final climb takes an hour. By this point, the trail is so steep that I have to haul myself upwards on ropes that have been knotted around gnarled roots and ancient trunks. The ground is wet and gloopy – and I repeatedly lose my balance in the miniature landslides that result from every footstep. It is only when I emerge, panting, into the clearing on the rooftop – and glimpse the neighbouring island of Montserrat 30 miles to the south-east – that I remember something crucial: I am in a part of the world where woozy relaxation, not strident exercise, is the general trend.
A torrid ascent of Nevis Peak may not be the standard Caribbean travel experience, but then Nevis is not the standard Caribbean resort island. It's a fragment of green amid a giant oceanic swirl of blue, an outpost that sits two miles south-east of its sibling in statehood, St Kitts, and 50 miles west of Antigua – but has little in common with either. Covering just 36 square miles, most of them slanted, it is tiny – not so much an island that has a volcano, as a volcano that happens to be viewed as an island. What counts as urban life plays out in villages on the coastal fringes where the terrain finally flattens, crowds and commotion notably absent. Even Nevis Peak, mighty in its stature, has the roar of a mouse. It has not erupted since prehistoric times.
This year, along with St Kitts, Nevis will quietly celebrate 30 years of independence from the UK. If it seems remarkable that the island did not cut direct ties with a foreign overlord until 1983, then its back story is even more worthy of comment – a rise and collapse that began with the first English settlers arriving in 1628 and saw Nevis bloom into one of the economic powerhouses of the Caribbean. Between 1640 and 1706, its sugar cane made it more valuable to England than both the fledgling colonies of Jamaica and America. It also became a hub of the dark trade in humanity, with more than 7,000 African slaves passing through every year between 1675 and 1730.
But in 1706, everything changed. When the French invaded, plantation owners burned their estates to keep them from the enemy. England retained control of the island, but the sugar industry found fertile fields elsewhere, and Nevis slipped into a financial slumber from which it has never really stirred. Even its name is an illusion carried on heat haze, a corruption of the Spanish nieve ("snow") – a word that may have been uttered by Christopher Columbus when he spotted the island (and its Amerindian Carib population) in 1493, but which certainly refers in error to the white fog that often envelops the peak.
The union with St Kitts – which came into being in 1882 – is an uneasy one. In a 1998 referendum, Nevisians voted, by three to two, to separate – a result that fell just short of the two-thirds majority required for secession. The two islands remain mismatched partners. St Kitts, twice the size, offers Caribbean clamour and noise in its busy capital, Basseterre (with its cruise terminal), and military history in the 17th-century Brimstone Hill Fortress, a Unesco World Heritage Site. Two miles across the aptly titled dividing channel, the Narrows, Nevis snoozes beneath cloudless skies.
This sleepiness is apparent as soon I step off the ferry in Charlestown. The Nevisian capital is a town in name only, its pretty clapboard houses reaching a mere three blocks back from the waterfront. Here, the Alexander Hamilton Museum opens one drowsy eye, its exhibits laid out in the birthplace of the island's most famous expatriate son, who became Secretary of the Treasury in George Washington's first US government.
This somnambulant pattern is repeated as, over the next two days, I explore. The island's homespun simplicity is visible in the road signs – "Undertakers Love Overtakers" is one – that sound more like admonitions from an elderly aunt than official rules of the highway.
On the east coast, it is hard to escape the notion that, if the clock did not quite stop in 1706, then it has not yet clicked around to 2013. Brick Kiln, a pinprick village, is a diminutive copy of Charlestown, its homes a merry rainbow of painted wood. Then there are the ghosts. Eden Brown Estate has – according to local tradition – been a damned location since 1822. On the eve of a wedding, the groom and best man (the bride's brother) quarrelled, and fought a duel that left both of them dead. When I step into the broken shards of the main house, there seems a residual sadness to the scene.
And there is further melancholy to New River Estate. Here, rusted cogs and ramshackle buildings mourn the island's last sugar plantation, which closed in 1958. The places stamped on to the abandoned machinery – London, Sheffield – tie the site to an industrial context 4,000 miles away. But the ocean view is entirely Caribbean.
Aside from my assault on the Peak, I devote five days to blissful indolence on the south side of the island. Here, the elegant retreat of Montpelier Plantation also sets itself aside from the standard Caribbean experience – by refusing to frolic in the surf. Instead, it perches on its lofty patch of grass, way above the waves (a shuttle-bus service ferries guests down to a private beach), as it has done since the plantation was created in 1687.
In some senses, very little has changed since. The hotel's 19 rooms seem to gaze back to a lost epoch. Of course, there are concessions to the 21st century – the large swimming pool at the heart of the complex; the cocktail bar alongside it. But the main house, where Restaurant 750 serves fine seafood, clings to the 18th century – a period when the plantation took a lead role in a love story. Between 1785 and 1787 it witnessed the courtship of Frances Nisbet, the owner's niece, and the young Horatio Nelson, then stationed in Antigua. Britain's greatest naval hero would find fame in the Napoleonic Wars, and notoriety in the arms of Emma Hamilton – but a small plaque here recalls that he married his wife in the gardens on 11 March 1787.
Montpelier Plantation's historic ambience will only become more appealing as the future begins to shake Nevis from its slumber. New major hotel developments are planned for the west coast, where a Four Seasons resort already does beachfront sophistication.
But when I head to the shoreline for dinner, I find the vibe still defiantly unhurried. Sunshine's, at Pinney's Beach, is one of those Caribbean hostelries where an evening can glide by in slow motion. The food – grilled snapper for US$20 (£13) – is tasty and informal. And the house cocktail, the Killer Bee (US$5/£3), involves a "secret" recipe (though the staple ingredient, without subtlety, is a lot of rum). To the north-west, the lights of St Kitts flicker. In contrast to the darkness that cloaks Nevis at this hour, the next-door neighbour could be a twinkling New York.
There is no obvious sense of urgency when I come to leave. My plane to Antigua is late. Very late. Two goats gnaw at bushes near the terminal. I retire to the café that skulks at the end of the runway, below the control tower. "You waiting for the Antigua flight?" asks the man on the chair in the shade. I nod. "Plenty of time," he grins, languidly indicating his walkie-talkie, which waits idle on the table. "I'll let you know."
I buy him a beer and we sip contentedly, watching breakers roll in just beyond the airstrip. And not for the first time in the week, I find myself questioning what year it is.
BA (0844 493 0787; ba.com) offers a daily service to Antigua from Gatwick, with flights on to St Kitts twice a week. Virgin Atlantic (0844 209 7310; virgin-atlantic.com) also flies to Antigua from Gatwick. Liat (001 268 480 5601; liat.com) provides a daily flight from Antigua to Nevis.
Montpelier Plantation (00 800 2000 0002; montpeliernevis.com). Doubles from $321 (£207), room only.
Guided hikes on Nevis Peak can be arranged via Montpelier Plantation – US$40 (£26).