The drizzle was getting stronger. We had reached Gran Canaria's misty, windy uplands, and the wide views and palm-tree sunshine of the previous two days now seemed part of another reality. "Right this minute, 20 kilometres away, people are drinking cocktails in hammocks," grinned local hiking guide Juan Carlos, as an Atlantic squall slapped wet ferns against our legs. I jammed my damp sunhat on to my head and we kept walking. "Just wait," he said. "Half an hour and the skies will be blue again."
He was right. Implausibly, we were reaching for the Factor 30 within minutes. Crossing Gran Canaria by foot involves three days, 75km and, as I was learning, the odd surprise.
I'd arrived here with manageable expectations. The volcanic island – on the map, a circular splotch sitting bang in the centre of the Canary Islands archipelago – enjoys renown for cheap winter sun, which means it is chiefly celebrated for the kind of holidays more associated with getting a suntan than pulling on hiking socks. The sandy beaches, like the happy-hour promotions, go on at length.
All of which makes Gran Canaria's new hiking route an intriguing prospect. To call it new, in fact, isn't strictly accurate. The tourist board has this year resurrected a centuries-old path between two of the island's holiest churches – located at Tunte in the centre and Galdar in the far north – prefixing it with a further day-hike to make it into a full coast-to-coast walk. Two pieces of advice: don't expect a simple stroll, and brace yourself for some stereotype-crushing panoramas.
"The shade is gone now, so keep drinking water," Juan Carlos said, two hours after the pair of us had set off. It hadn't taken long for the surroundings to feel remote. Our trek had begun in the centre of Playa del Ingles, the south-coast resort which acts as the epicentre of the island's package-tour industry. At 9am we'd been walking past pizzerias, show bars and mini-golf courses. At 11am, by contrast, high-reaching bluffs hulked above us and the sun thumped down on cactus groves. The heat was already thick. Two rabbit-hunters in the scrub provided the only other sign of humanity astir.
The thing with volcanic islands is how readily the scenic drama gets ratcheted up. Gran Canaria is the result of a thunderous discharge of rock and magma, a titanic prehistoric belch of fire and basalt. It was shaped between 12 and 14 million years ago (the youngest Canary Island, El Hierro, is a comparatively sprightly one million years old).
Despite its limited diameter, Gran Canaria reaches heights of 1,950m, so once you head into the interior, the panoramas cleave and unfold in all directions at once. By early afternoon – and following a finger-purpling feed on wild prickly pears – we'd climbed a steep path up to the lofty hill pass of Degollada de la Yegua. Lying around us was a raw spread of gorges, ridges and lush oases. Kestrels flew in the gullies below. The notion of Gran Canaria as little more than a brochure's-worth of pool loungers was already consigned to dust.
The island is remarkably fertile. Even up here, the trail was flanked by sage, sorrel and thyme, and smallholding orchards hung heavy with almonds and oranges. The path wound down greenly into the cobbled, whitewashed village of Tunte (often marked on maps by its administrative name, San Bartolome de Tirajana). The restorative, and dangerously cheap, arms of cold beer and hot tapas closed around what had been a tiring nine-hour day – the hardest and longest, it would emerge.
Tourism is the most important industry on Gran Canaria, but 30 years ago the picture was different. The collapse of the island's banana and tomato export markets has resulted in high unemployment rates. Visitors have become more prized, making it all the more surprising that so few of them are enticed to visit the momentous peaks and quiet townships of the centre. Indeed, if Day One had impressed, then the walk from Tunte to the settlement of Tejeda was better still. The cliffs were steeper, the calderas deeper and the trails more alluring. So much so that a stray dog who padded alongside us after breakfast was still with us, bright-eyed, at day's end. "We must call him Peregrino," Juan Carlos said. "Pilgrim."
The spiritual element to the cross-island walk will certainly be of interest to some – the attractive old-world churches at Tunte and Galdar are both dedicated to Santiago (St James), making this a mini-me version of Spain's grander Camino de Santiago – but the emphasis is on the walk itself. The second day culminated, in fact, with the wildly beautiful landscape that had enthralled native settlers long before Spain, and Christianity, claimed the land in the 15th century. The rutting, rolling Tejeda district is gathered around the craggy might of the 1,400m-high Roque Bentayga – for generations the site of pagan rituals – and makes for the kind of sight more synonymous with African foothills than fun-in-the-sun boltholes.
Tejeda itself, where we passed the night at the excellent Hotel Fonda de la Tea, is a warm, go-slow village of bougainvillea and unrushed old men in crisply ironed shirts. From its main square I was presented with a perfect profile of Tenerife on the ocean horizon. Locals are fond of saying that the best views of that island's Mount Teide volcano, the highest point in Spain, are from Gran Canaria. The boast winds the Tenerifeans up, and says plenty about lusty local pride. "I am Spanish, but I never introduce myself without adding that I am Canarian," one hotel owner stressed to me.
Peregrino stayed with us for the final day too. He must have known that the wind and rain of the northern highlands – not a given, it should be said – would lead back into sunny valleys. The island's meteorological oddities are caused by the trade winds blowing in from the north-east, the same breezes that brought Columbus to the island and turned its capital city, Las Palmas, into a key transatlantic stopover. It means clouds gather in the north, trapped by the hills. An hour of mist felt like an acceptable price to pay.
The long, draining descent into the coastal town of Galdar took us through lichen-hung pine forests. It felt a world away from the red rocks of the far south. The views were still broad and the hills still looming, but the countryside curves were softer now, and the sea more dominant. We continued down until dirt trails became asphalt and vineyards gave way to houses. A last, sadistic slope led us into the town centre and journey's end. Almost too perfectly, there was a wedding drawing to a close at the church. "So," Juan Carlos said, as we collapsed in the park and watched the rice and confetti fly. "Shall we walk back now?"
You can fly from a wide range of UK airports to Las Palmas, the main airport for Gran Canaria (and the whole of the Canary Islands). Ryanair (0871 246 0000; ryanair.com) and Monarch (08719 40 50 40; flymonarch.com) are the main airlines. In addition, easyJet (0843 104 5000; easyJet.com) flies from Gatwick.
The tourist board has a website dedicated to the three-day trek (bit.ly/vXVOcG), and the tourist office at Playa del Ingles is able to provide maps and further details of route and accommodation options. Full signposting is unlikely to be finished until spring 2012. See grancanariafincas.com for more hiking information.
The writer stayed at the Sheraton Salobre in Maspalomas (00 34 928 943 000; sheratonsalobre.com; doubles from €180), La Hacienda del Molino in Tunte (00 34 928 127 344; lahacienda delmolino.com; B&B from €70), Hotel Fonda de la Tea in Tejeda (00 34 928 666 422; hotelfondadelatea.com; B&B from €86) and Las Longueras Hotel in Agaete (00 34 928 89 81 45; laslongueras.com; B&B from €100).