The world's top cyclists are set for the most punishing Tour de France in recent history after gasps from the audience greeted the unveiling of next year's route.

Jaws dropped at the Palais des Congres in Paris on Thursday when Le Tour race director Christian Prudhomme revealed the course for next summer's event, staged from July 1st to 23rd.

There are eight flat stages, but also eight out-and-out mountain stages with four summit finishes, plus several more hilly days and only one individual time trial - and even that ends in the skiing resort of Combloux.

It looks a brute of a course, plays firmly into the hands of the climbers and will certainly ask plenty of questions of defending champion Jonas Vingegaard.

What	Tour de France 2023
Where	Bilbao to Paris
When	Saturday, July 1st - Sunday, July 23rd, 2023
How to watch	FloBikes

Bilbao beckons for rare Spanish start

Thirty-one years after the Tour de France last started in Spain, the peloton will gather in Bilbao on July 1st for the Grand Depart of the 2023 edition.

It's a 182km ramble through the Pyrenees, it will be hilly - there are five categorised climbs - and that sets the tone for one of the lumpiest Tours in living memory.

Vingegaard, the man who prevailed against the odds by dethroning the apparently invincible Tadej Pogacar and who looked outstanding in the mountains, is -110 to keep his crown, with Pogacar at +137.

But it will be interesting to see how the teams figure out their rosters for next year's Tour given the Giro d'Italia in May might appeal more to all-rounders with slightly less time spent in the mountains and three time trials.

Will anyone erupt en route to the volcano?

The first week of racing features three days in Spain with the third of those stages ending in Bayonne on the French Atlantic coast.

Stages five and six are the days when the peloton confronts the big mountains in the Pyrenees.

Stage five features the Col de Soudet and Col de Marie Blanque on the way to Laruns and then, 24 hours later, the field will have to top the Col d'Aspin and the legendary Col du Tourmalet as they ride from Tarbes to Cauterets Cambasque.

A couple of days for the sprinters - and the first real chance for Mark Cavendish (if fit and selected) to claim that record-breaking 35th stage win - precedes the first ascent of the dormant volcano Puy de Dome since 1988 on stage nine.

The final four kilometres - at over 11 per cent - used to be closed to the public which made for an eerie spectacle, but that could change on July 9th.

Alpine ascents will split the field

Week two after a rest day is all about the Alps with a trio of famous finishes at Grand Colombier, Morzine and Saint-Gervais Mont Blanc.

The 14.4km haul of Grand Colombier is on Bastille Day - July 14th - so wouldn't the French just love to roar one of their own up those final, draining few yards to the line. David Gaudu, for example, who is +4000 to win the Tour, or Romain Bardet (+6600).

There are six climbs on stage 14 between Annemasse and Morzine while the battle up to Saint-Gervais a day later features some sections at around a numbing 17 per cent.

Time trial before procession in Paris

That second rest day will be welcomed and is followed immediately by the only time trial of the tour, just 22 kilometres and all ups and downs from Passy to Combloux, with the one main climb featuring a section at around 16 per cent.

They stay in the high mountains for stage 17, reaching the high point of the race at Col de la Laze, where Primoz Roglic distanced Pogacar in 2020 (to no avail as it transpired).

And to ensure the race is taken almost to the wire, there is no last-ditch time trial on the Saturday before the processional parade around Paris, instead organisers have opted for a 133km run through the Vosges up to a ski station at Le Markstein.

It is a brutal end to a brutal schedule and no wonder two-time winner Pogacar broke into a smile when the route was unveiled on Thursday.

Whether or he not he'll still be laughing up the Champs-Elysees on July 23rd remains to be seen.