Chris Froome may be the favourite to earn another Tour de France title, but the Team Sky leader and defending champion faces a battle to finish in yellow once again.
Froome himself has suggested at least 10 riders could challenge for general classification glory in a wide open peloton.
Ahead of stage one of the 2016 Tour, from Mont Saint-Michel to Utah Beach, we look at the top five contenders, starting with two-time champion Froome.
CHRIS FROOME (TEAM SKY)
Having finished runner-up to Bradley Wiggins in 2012, Froome assumed the number-one role at Team Sky 12 months later and has since led them to another two Tour victories.
The Kenya-born Briton held the yellow jersey from stage seven last year and was able to take victory by over a minute - although Nairo Quintana pushed him hard - with some impressive performances in the mountains.
Froome has six top-four finishes in his last eight Grand Tour appearances, and was involved in a gruelling training camp with Tim Kerrison in Mallorca ahead of the 2016 season.
He has enjoyed two race victories in four outings this year, the 31-year-old keen to remain fresh for a climb-heavy Tour.
His third Criterium du Dauphine win last month provided encouraging signs, Froome winning stage five to secure the overall win by 12 seconds from Romain Bardet.
Froome also took victory in the Sun Tour at the start of the year, and picked up a stage win during the Tour de Romandie.
NAIRO QUINTANA (MOVISTAR)
Quintana has firmly established himself as a Grand Tour contender in recent years with strong performances in all three races - the Colombian winning the 2014 Giro d'Italia.
He was fourth in the Vuelta a Espana last year, while he has finished as the runner-up to Froome on each of his Tour de France appearances to date, in 2013 and 2015.
The Movistar leader will almost certainly be in contention once again this time around, with many - including Froome - suggesting the route suits his style perfectly.
Another factor making him a likely challenger for a first Tour win is his form in 2016, Quintana having enjoyed more wins than any of his rivals.
After finishing third in the Tour de San Luis, the 26-year-old recorded three successive race victories at the Volta a Catalunya, Tour de Romandie and Route du Sud.
ALBERTO CONTADOR (TINKOFF)
While Quintana is the young pretender within the peloton, Contador is the elder statesman not afraid to battle it out with the next generation.
The 33-year-old will be racing in his ninth Tour - although two of his appearances have since been struck from the records - and, like Froome, is looking for his third yellow jersey.
Contador has not won since 2009, but has finished fourth and fifth in the last three years.
The Spaniard has spent much of 2016 discussing his future and announced ahead of the Tour that he would postpone his retirement again, although he will leave Tinkoff at the end of the year.
Second places in Paris-Nice and the Volta a Catalunya have shown he still has it in his legs to compete, and he was in contention at the Dauphine before Froome took control.
FABIO ARU (ASTANA)
Vincenzo Nibali's heir-apparent is making his debut at the Tour this year and Aru will have the aforementioned Nibali to guide him through the three weeks.
The least experienced of our five contenders, Aru still holds an impressive Grand Tour record with top-five finishes in his last four big races - including a breakthrough win at the 2015 Vuelta a Espana.
His results have not been so impressive in 2016, sixth place at the Volta a la Comunitat Valenciana representing his best finish so far.
He did place inside the top-10 at the Volta ao Algarve and won a stage at the Dauphine, but he has yet to contend for general classification honours this year.
The Tour will be a big test for Aru's growing reputation. Should he struggle under the pressure, Astana could turn their focus to Nibali, even though the latter has Olympic gold in his sights.
RICHIE PORTE (BMC RACING)
Porte's place in the top-five contenders is borne out of the fact he has played such a pivotal role in each of Froome's successes.
The Australian's role as Froome's lieutenant during his three years at Team Sky made him worth the gamble for BMC Racing, and he will co-lead the team with Tejay van Garderen.
Due to his previous roles at the Tour, Porte has only one top-20 finish to his name, but his results do not tell the full story and his competitiveness in the mountains could make him a real challenger.
He started his BMC career with a second-place finish at the Tour Down Under, before going on to claim third at Paris-Nice and fourth in the Ciclista a Catalunya.
Porte showed his ability to fight for top spot more recently at the Dauphine, the 31-year-old sitting in the top three of the overall classification until a tough final stage.
That saw him fall behind Romain Bardet and Dan Martin to finish fourth, his old friend and now adversary Froome taking the win.