After the relative calm of the Austrian Alps, the bustle of Le Bourg D’Oisans on market day feels almost overwhelming. Thousands of tourists amble through the town, pausing to refuel at patisseries and street cafés as they stroll between stalls selling everything from massive slabs of Gruyère to budget sports socks.

This is a town that revolves around cycling. It sits in the shadow of the iconic Alpe d’Huez and within easy reach of many other famous cols, including the Croix de Fer, the Glandon, the Telegraphe and the magnificent Galibier. It’s the starting point of the infamous La Marmotte sportive ride – about which cyclists speak in hushed tones because of the savagery of the parcours, taking in just over 5,000 metres of climbing in 177km.

La Marmotte might be tough, but the fourth parcours of the seventh Transcontinental Race is tougher, climbing just as much – up some of the same cols, in fact – but over 50 fewer kilometres. And let’s not forget that by the time the riders hit this parcours, they’ll have covered more than 2,500km with nowhere near enough sleep; they’ll be tired, sore and their bodies will be screaming at them to stop.

But they’ll also know that this marks the end of the serious climbing in #TCRNo7. They’ll know that if they can just hold on for a few more days and pace themselves right for the 1,100km drag across France to the finish line in Brest, their race will be over.

Race leader Fiona Kolbinger reached control point 4 on the terrace of the Hotel De Milan on the Rue Général de Gaulle just after 1pm on Saturday – around eight hours before second-placed Ben Davies. She looked as fit and fresh as anyone could possibly dare to hope they’d look after riding 2,500 gruelling kilometres in a week.

After having her brevet card stamped, she shared the unexpected information that she sometimes sings to herself as she rides. During the TCR, she said, her favourite tunes were Highway to Hell and Staying Alive. She was feeling good, despite the 30+ degree heat. And this parcours had been her favourite so far.

Then she popped into the hotel for some essential personal maintenance. But before disappearing, she sat down at the lobby piano and played a passable rendition of The Lion Sleeps Tonight – possibly the most surreal moment of the race so far.

Behind Fiona, the race for third place is becoming intense. After an enforced pause at CP3, Sam Thomas lost his advantage, and now lags behind a group of riders that includes Job Hendrickx, Pawel Pulawski, David Schuster and Kosma Szafraniak among others. Not far behind them, three of the remaining fizik ambassadors – Alex Jacobson, Matt Falconer and Levy Bagoly – are all riding well, a few hundred kilometres ahead of the fourth, Cento Bressan.

After the fourth control point, the parcours continues up the tough Col du Solude, a 12.5km climb with an average gradient of 7.5% with several sections steeper than 10%. It’s a prospect that Fiona dismissed with a shrug. “That’s not a hill – more of a hump.”

After that the mountains are done with and it’s time for the long haul across France. The end of this epic race draws near. Fiona Kolbinger’s lead looks unassailable. But this is the Transcontinental – anything can happen.