A while ago I rode the route that a TdF stage was to take a fortnight or so later. At the start of the road over Puy Mary the snow signs said it was shut. Since there was no snow anywhere else and my alternative was very long way round, I ignored the signs and carried on.
Nearing the pass an ever-increasing number of heavy lorries thundered by, carrying tarmac and when I finally reached the foot of Puy Mary I realised they were resurfacing the road all the way up to the summit. At the scene of operations it was like hell, the heat from tar, the demonic activity of those doing the work and the noise..
Fortunately I was able to get through, just but I have never seen roadworks being done at such a pace, almost entirely for a stage of the TdF. I reckon that road must have been shut for nearly 3 weeks.