After a very long night, the culminating afternoon of this year's 24 Heures du Mans sees bleary eyes revitalised by the looming chequered flag and a late curveball in the form of some heavy showers during the closing stages.

The inclement conditions shake up the GTE Pro class, relegating Aston Martin Racing's number 97 Vantage V8 from first place to third as both Team Manthey-run factory Porsche 911 GT3s capitalise on better tyre strategies. The top spots in the other divisions are unaffected, though, with Tom Kristensen bringing home the Audi R18 to win LMP1 for team-mates Allan McNish and Loic Duval, OAK Racing's Nissan-engined Morgans taking a one-two in LMP2 (with British drivers Martin Plowman and Alex Brundle involved respectively) and the IMSA Performance 911 GT3 taking the GTE Am win. Celebrations are understandably subdued in the light of Allan Simonsen's tragic passing on Saturday, with an emotional Kristensen dedicating the win to his fellow Dane.

We join the hordes trickling away from Circuit de la Sarthe and begin our return journey to Brands Hatch, this time at the wheel of an Alfa Romeo Giulietta 1750 TBi Cloverleaf after Friday's outward trip in an Audi R8. I agree with my car-mate that, given the chance to visit again, a Sunday night stay might be preferable, allowing the chance to relax, convalesce and get some sleep before a less-congested Monday retreat. As it is, we spend the next few hours eroding the autoroute slog to the Eurotunnel terminal at Calais. Most motorway bridges and many toll plaza verges host waving, picture-taking groups of car fans out to see what exotica the homeward-bound convoy will bring. They're not disappointed, and neither are we – we pass a 1981 Aston Martin V8 Vantage, its flanks splattered with Le Mans car park mud, the mid-journey crossing of the Seine at Rouen delivers a showroom-condition white Audi Sport Quattro that has us drooling, and droves of modern supercars check in at Calais.

The Alfa serves us well with its 'DNA' driving mode selector in normal (or 'natural', insists Alfa) to settle the steering. The ride is a tad jittery when cruising, but acceptably so given the Giulietta's decent handling skills that get a brief workout during the last few soggy miles to Brands. The 1742cc turbo four-pot under the car's shapely bonnet impresses with its appetite for revs, and doesn't feel at all stressed when delivering its peak output of 231bhp. A revised, 237bhp version of the same engine will appear in the gorgeous, 220kg-lighter Alfa 4C coupé that's due in August, and if the exhaust note can be spruced up appropriately, I think it'll fit in nicely.

The 63 hours since we left Brands Hatch have felt like at least a week – it's been a trip packed with diverse experiences from the journey in the R8 to the drivers' parade in old Le Mans, the start of the big race, the late-night/early morning atmosphere at Circuit de la Sarthe and Sunday's finale. It's remarkable to think the race itself lasted for almost one-third of our entire trip, which puts our tiredness into perspective against the endurance demonstrated by the teams, drivers, circuit staff and, indeed, the cars – the winning machine having covered nearly 3000 miles. There are other endurance races, but this weekend has shown me there's nothing quite like Le Mans.