Stretching for 4,800km, from British Columbia, in Canada, to New Mexico, in the United States, the Rocky Mountains are one of the most spectacular and accessible ranges on the planet. With 30 of its highest peaks, the Colorado section is an incredible outdoor playground.

Although the peaks are blanketed in snow for a large part of the year, when the meltwater has finally turned streams back into torrents and lakes and reservoirs into water-sports venues, 2,000 cyclists take to the roads and mountain passes of the Centennial State for Ride the Rockies, an annual 720km, seven-day cycling adventure.

The route changes every year and, in 2017, it started in the south-central part of Colorado, on the eastern side of the American Continental Divide, in Alamosa.

Founded by the Denver and Rio Grande Railroad in 1878, Alamosa is home to fewer than 9,000 people. As with many small towns in this part of the country, it doesn’t take much imagination to envision its Wild West past; a stroll around the historic downtown takes the visitor past beautiful late Victorian, Mission Revival and art deco buildings.

Colorado’s Two Rivers Winery, for fans of wine and white-water rafting

Boxing enthusiasts might want to take a 50km drive south, to the town of Manassa, the birthplace of Jack Dempsey, arguably the greatest heavyweight of all time. The Jack Dempsey Museum is housed in the actual cabin where the sportsman was born and has on display boxing gloves and shoes among other artefacts from the Manassa Mauler’s career.

Day one and the cyclists trickle out of Alamosa heading west. A gradual 80km stretch is followed by an exhausting 28km climb (fuelled by a potato provided free of charge at a refreshment stop by Colorado growers) to Wolf Creek Pass, at 3,300 metres. By the time riders start their 40km descent into Pagosa Springs, an emerald green valley dotted with spruce and pine, the plains of Alamosa feel as though they are a long way back.

Just 55km from the New Mexico border, Pagosa Springs has a population of less than 2,000 people and is nestled among the three million acres of the San Juan National Forest and the Weminuche Wilderness. It is fed by the natural hot springs that give the town its name – pagosah means “healing waters” in the language of the South­western Ute tribe, native to the region.

A soak in one of the three resorts is essential after a day in the saddle. The quaint Overlook Hot Springs is across the San Juan River from the larger Springs Resort & Spa, billed as the deepest geo­thermal hot spring in the world. Visitors simmering gently in the resort’s mineral pools – the Lobster Pot is the hottest, at about 44 degrees Celsius – are afforded expansive views over the town and river.

Some 110km from Pagosa Springs is the finish line for day two, in Durango. Also founded by the Denver and Rio Grande Railroad, the town is at one end of the Durango & Silverton Narrow Gauge Railroad and was the location for several key scenes in the 1969 movie Butch Cassidy and the Sundance Kid.

The steam locomotive still rumbles through the San Juan Mountains to the old mining town of Silverton and back, as it has done since the 1880s, but these days it carries passengers rather than silver and gold ore. Cyclists are invited to race the train every May, as part of the Iron Horse Bicycle Classic.

Day three of Ride the Rockies involves an untaxing 63km loop around Durango that some riders use as a chance to explore and rest up ahead of the most difficult day (perhaps also the most rewarding in terms of scenery): 134km and 2,380 metres of elevation over three mountain passes and a speedy descent into the town of Ouray and on to Ridgway, which, when it arrives, is a sight for sore eyes – and a relief for sore legs.

High and mighty: Colorado

By this stage, most riders are beyond caring about the history of the places through which they ride. For a time, though, Ridgway and the surrounding area were, much like Durango, in favour with movie producers, hosting the like of James Cagney in Tribute to a Bad Man (1956) and John Wayne et al in True Grit (1969). The latter film’s gruesome hanging scene was filmed in grassy, tree-lined Hartwell Park, which has now been transformed into a mini-festival site, with arts installations and live music.

A short ride the following day means a lie-in. With so many people passing through – including hundreds of riders’ friends, family and support staff – all hotel and Airbnb accommodation in the small towns is occupied. Hundreds more camp at established “HQs” and a fair few riders sleep in their support vehicles.

Next stop, Montrose, home to Gunnison National Park and its Black Canyon, which contains some of the steepest cliffs, oldest rock and craggiest spires in North America.

Named by an admirer of Sir Walter Scott’s novel A Legend of Montrose (1819), the town of about 20,000 people was, for a brief period, a name uttered with some reverence in civil-engineering circles, thanks to the Gunnison Tunnel. Riders cannot actually see it, but interpretive signs along East Portal Road tell the story of what was – at the time of its completion, in 1909 – the longest irrigation tunnel in the world, and which turned arid land into profitable agricultural tracts.

The penultimate day takes riders towards Gunnison, along the shores of the Blue Mesa Reservoir, the largest lake in the state. Part of Curecanti National Recreation Area, a series of three reservoirs along the Gunnison River, this region is a draw for sailors, salmon and trout fishermen, hikers, campers and bird watchers. Two climbs and beautiful, lush green scenery brightened with wildflowers make this one of the most rewarding days in the saddle.

Denver’s ART hotel, where it feels like you’re sleeping in a gallery full of modern masterpieces

With a sense of relief and excitement, riders gear up for one last push, leaving Gunnison for a gradual 56km, followed by a 16km climb and a 32km descent, crossing the Continental Divide once more, at Monarch Pass, which is compar­able to Tai Mo Shan, the toughest ascent in Hong Kong. The humidity is certainly higher in Hong Kong, and the shrubbery and scenery are different, but your legs ache just the same.

Having climbed 1,200 metres in total on the final day, the riders that are still pedalling (this not being a race means most complete the course) cruise into Salida – the Spanish word for “exit”, appropriately – to enjoy the sense of achievement.

Iceland the hard way – Hong Kong friends cycle country’s coastline for ‘fun’

Who won? Who cares! Completing the seven days is considered a victory in itself. In fact, the star of the event is the last person to cross the finish line, a 67-year-old priest from South Dakota, who is given a police escort and a round of applause in Salida’s Thonhoff Park by his fellow Rockie riders.

Entry to Ride the Rockies (ridetherockies.com) is allocated through a lottery. Ride the Rockies 2018 will be held from June 9 to 16. Registration opens in February.