The 3,358.1-kilometre (2,086.6 mi) race included 21 stages, beginning in Marbella on 22 August 2015 and finishing in Madrid on 13 September.

The average age of riders in the Vuelta was 29.13 years, ranging from the 20-year-old Matej Mohorič (Cannondale–Garmin) to the 38-year-old Haimar Zubeldia (Trek Factory Racing).

[19] There was a similar situation at Movistar, as Valverde, who had won the Vuelta in 2009 and had finished on the podium on four other occasions, was also in strong form and was well suited to the course.

Nacer Bouhanni (Cofidis), who had crashed out of the Tour, was expected to compete with Degenkolb in the flat sprints.

[21] More news came the following month, when Guillén revealed that he had been involved in conversations with Chris Froome and had promised him that the race would include a fairly flat individual time trial of around 40 kilometres (25 mi).

[22] The official route announcement came on 10 January 2015 in Torremolinos, along the coast from the start of the first stage in Puerto Banús.

The sixth stage started in Córdoba and finished in Sierra de Cazorla in Jaén on another moderately difficult climb.

The seventh stage then returned to Andalusia for the first major difficulty of the race: the first-category summit finish at La Alpujarra.

It was therefore expected that the climbers would need to attack early in the race, in order to build up a significant lead ahead of the lengthy time trial on Stage 17.

The race organisers also hoped to encourage sprinters to take part by including seven fairly flat stages.

On arriving at the start, the teams discovered that the route used a variety of road surfaces, crossed sandy sections and included several ramps.

After the stage, a video emerged of Nibali holding on to his team car as it accelerated him back to the peloton.

Peter Sagan won his first Grand Tour stage in over two years ahead of Nacer Bouhanni (Cofidis) and John Degenkolb (Giant-Alpecin).

The relatively straightforward stage was won by Caleb Ewan (Orica–GreenEDGE), who was riding his first Grand Tour, ahead of Degenkolb and Sagan.

Most of the general classification favourites finished together, though Fabio Aru gained seven seconds in the final kilometre and Chris Froome lost nearly half a minute.

Four riders were immediately forced to withdraw from the race with injuries, including Dan Martin, who had been in the top ten.

The stage was won in a reduced bunch sprint by Jasper Stuyven (Trek Factory Racing), who had been among the riders injured in the earlier crash.

Tom Dumoulin eventually took a solo win in the stage, two seconds ahead of Chris Froome, and took back the red jersey as Chaves lost significant time.

[43] Chris Froome fell from his bike at the beginning of the stage and lost several minutes to Aru; the following morning it was revealed that he had broken his foot in the fall and he withdrew from the race.

[43] The following stage, which took the riders from Andorra back into Spain, was won in a sprint by Danny van Poppel (Trek Factory Racing) after the day's breakaway was caught in the final kilometre.

[45] The thirteenth stage – the last one before a series of three consecutive summit finishes – was won from a breakaway by Nelson Oliveira (Lampre–Merida), with no impact on the general classification.

[46] The first of the three summit finishes – Stage 14 – was won by Alessandro De Marchi (BMC Racing Team), who had been in the day's breakaway.

[47] Rodríguez attacked strongly on the final climb to win Stage 15 and gained time on all his rivals, putting himself just one second behind Aru.

Nicolas Roche (Sky) won Stage 18, beating Haimar Zubeldia (Trek Factory Racing) in a two-man sprint.

It was won by Alexis Gougeard (AG2R La Mondiale), who had escaped from the breakaway group on the previous climb.

At the end of the stage, Dumoulin used his team to put him in a strong position for the cobbled climb and he increased his lead over Aru to six seconds.

During the stage, Valverde took advantage of a puncture for Rodríguez and won the intermediate sprint to give him the points jersey.

Although Aru lost a little time in a split in the peloton at the finish line, the rest of the standings were unchanged.

Stages were categorised as third-, second-, first- and special-category, with the more difficult climbs rated higher.

The most difficult climb of the race, the Alto Ermita de Alba on Stage 16, was given its own category as the Cima Alberto Fernández.