With Tour de France 2019 rumours abounding, there has been speculation a mountain time trial could feature.
Mentions of a summit finish on the Tourmalet or a possible time trial in Pau have prompted the suggestion riders could go solo to the summit of the col.
Race organisers are embroiled in attempts to reinvent stages of the biggest races, and mountain time trials could be one of the answers.
In an attempt to reinvigorate the mountain stages, this year’s Tour de France featured at 65km mountain stage with a grid start, while the Tour de Romandie organisers included a 9.9km picturesque uphill time trial on stage three.
Take a look back at the history of Tour de France mountain time trials:
1958 - Mont Ventoux
The iconic slopes of Mont Ventoux set the scene of battle for stage 18 of the 1958 Tour.
By that point in the race the yellow jersey had been held by seven different riders, but it was Luxembourg’s Charly Gaul who would make headlines that day.
The 21.5km course was a run from Bédoin to the summit of Ventoux, and Gaul smashed his competition to finish 31 seconds ahead of Spanish rider Federico Bahamontes and bring himself back into contention for the overall.
Gaul took the yellow jersey two days from the finish on stage 22 and rode to victory in Paris.
1962 - Superbagnères
But Bahamontes would get revenge for the Ventoux TT loss four years later.
The Spaniard won the mountain solo stage from Luchon to Superbagnères on stage 13.
Bahamontes finished the 18.5km day 1-25 up on Joseph Planckaert from Belgium and 1-28 ahead of French legend Jacques Anquetil, who went on to take the yellow jersey that year.
Gaul was 1-29 down in fourth.
Britain's Tom Simpson led the race after the previous stage but lost the yellow jersey during the time trial, finishing 5-30 down on the stage winner in 31st place.
1965 - Le Revard
Then three years later the mountain time trial returned, this time on stage 18 from Aix-les-Bains to Le Revard over 26km.
That day was taken by the dominant yellow jersey, Felice Gimondi from Italy.
Gimondi held the yellow jersey from stage three, lost it for two days on stage seven, before reclaiming the lead and carrying all the way to Paris.
He finished 23 seconds ahead of Frenchman Raymond Poulidor on the mountain time trial, who would finish second overall that year.
1987 -Mont Ventoux
The Ventoux time trial returned on stage 18 of the 1987 Tour, this time with a longer 36.5km test.
Frenchman Jean-François Bernard was the victor that day, taking 1-39 out of his nearest rival Luis Alberto Herrera from Colombia.
The eventual winner of the Tour, Ireland’s Stephen Roche finished fifth atop the mountain, 2-19 down on the stage winner and 30 seconds down on Pedro Delgado, who finished second at the end of the Tour.
1994 - Avoriaz
Another uphill battle against the clock played out on stage 19 of the 1994 Tour de France.
This ITT was a long-distance 47.5km from Cluses to Avoriaz in eastern France.
Latvian Piotr Ugrumov won the day, making it his second consecutive stage win.
Marco Pantani came in 1-38 down on Ugrumov, followed by that year's Tour winner Miguel Indurain.
2004 - Alpe d'Huez
Stage 16 of the 2004 Tour featured a time trial on another of cycling’s most historic climbs – Alpe d’Huez.
Lance Armstrong was the only rider to break the 40 minute mark on the road to the summit, riding his way to a sixth Tour de France victory.
Armstrong had dubbed the stage ‘crucial’ before the race and put in an unbelievable ride to take the stage win, with a minute on nearest rival Jan Ullrich.
Of course, Armstrong’s ride was too good to be true, and he was later stripped of all seven of his Tour de France victories.
2016 - Megève
Now to more recent history, and the 2016 race included another late mountain time trial on stage 18.
This time the individual test rose 17km to the Côte de Chozeaux before a slight downhill kick to Megève.
Team Sky’s Chris Froome was the man of the day, taking the stage win with 21 seconds to spare over Dutchman Tom Dumoulin riding for Giant-Alpecin.
Froome held the yellow jersey from stage seven and carried the victory to Paris to claim his third Tour title.
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