The card boasts six Group 1 races aside from the Arc and we'll take a look at the key contenders in those races here, starting with the Prix Marcel Boussac over a mile for three-year-old fillies.
Timeform Top Rated: Ballydoyle
The market points to this being a battle between the French filly Antonoe and Ballydoyle's Ballydoyle.
The ominously named Ballydoyle was turned over by her less-fancied stablemate Minding in Ireland last time but her win prior is the pick of the form on offer in this and with quicker ground predicted at Longchamp she should be back at her very best. The step up to a mile also looks a big plus for the sister to 2010 winner Misty For Me.
Antonoe has looked very smart winning a couple of lesser races and doesn't have to make too much of a leap to make it interesting.
Click here for full form, speed maps, and ratings for Longchamp's Arc Meeting
There looks to be more depth in the colts division - the Prix Jean-Luc Lagadere.
Timeform Top Rated: Herald The Dawn
Aidan O'Brien is again prominent here with current favourite Johannes Vermeer appearing the stable number one seed.
He impressed winning well last time out on Irish Champions Weekend and the future appears very bright. He bumps into a couple of Group 2 winners here in Herald The Dawn and Galileo Gold who set a good standard.
Ultra runs for Andre Fabre and he plays a similar role in this to the one that Antonoe plays in the opener. Two from two in minor events and with plenty of upside on form that is working out quite well. He could be very smart.
The mares go around in the Prix de L'Opera over 2000m.
Timeform Top Rated: Odeliz
British fillies and mares have had a good time of it coming over to France this season and that may well continue with a couple prominent here.
Jazzi Top won the Prix de la Nonette in good style and looks to arrive here still on the improve while Odeliz skipped across the pond and won the Prix Jean Romanet in August and that should have her right in the mix here. Looks over the odds at around 12-1.
The Irish Oaks winner Covert Love was brave at Yorkshire last time but has to come back to 2000m now.
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Prix De L'Abbaye
Timeform Top Rated: Muthmir
The Abbaye has already lost some gloss with the scratching of Mecca's Angel on account of the expected firm ground.
Firm ground will be no concern for Muthmir, however, and a return to his Goodwood form on such a surface would likely prove good enough for him to come out on top.
Sole Power got back to winning ways last time and always has to be respected in these 1000m features. He runs in this race for the fifth straight year and while he has never come away with the prize he has run well in each of the last four runnings.
The Prix De La Foret is the chance for Limato to grab a Group 1 success that, in truth, had been expected to come earlier than this.
Timeform Top Rated: Limato
Limato was no match for top-class sprinter Muhaarar in the inaugural Commonwealth Cup at Royal Ascot, a race that had his name on it for the best part of six months in the lead up.
Having been beaten there, and then off the scene for three months, it might have looked like the top two-year-old of last season's ship had sailed but he returned at Doncaster and slammed a Group 2 field with a Group 1 performance last time and now looks ominously poised heading into the Foret.
He rates head and shoulders above his main rivals Toormore, Custom Cut and Make Believe.
The Prix Du Cadran over 4000m brings the day to a close.
Timeform Top Rated: Bathyrhon
A wide open finish to the day. Bathyrhon finished second in the race last year and has been every bit as good in 2015.
He was smashed in the Foy last time but all of these would have been, they simply don't run fast enough, and he should be back in the shake up with the emphasis right back on stamina here.
Walzertakt has knocked him off this year and has to be seen as a good hope of doing just that again. He's the key danger
