I'm surprised that this hasn't yet been done by anyone here, or indeed as an ITT. Looks pretty epic:

http://www.grande-traversee-alpes.com/e ... -du-soleil

I've ridden a short section while on a family holiday the other year. It would be a (nother) great route to ride though.

Good site, it's been updated a bit by the look of it? We rode the GTA Geneva-Nice road route in 2011, that was a great ride. Then used the site as part of the planning for an MTB version, ended up doing a route based on the Geneva-Nice GR5 and some variations on it. http://www.moveyouralps.com/en/gr5-alps ..Recommended. Best ride I've done. Can't link a route as we just used maps and made it up as we went but I have been back on google earth to map some of the sections as I'd love to re-ride a similar but different version of it.

Presumably you have to detour round the national parks where VTTing isn't allowed and the GR5 passes through them?

How much Hike-a-Bike in the actual GR5 route (or whatever you did)?

I've ridden parts of this route and it's bloody lovely!

There are a few (4 or 5?) books covering the various sections of the route from:

http://www.vtopo.fr/

In French but the maps are good (uses the French IGN mapping) and there's loads of info about variations, supply points and other helpful bits and pieces.

I keep meaning to return to do a bigger multiday trip but so far sufficient time hasn't magically presented itself.

Presumably you have to detour round the national parks where VTTing isn't allowed and the GR5 passes through them?

How much Hike-a-Bike in the actual GR5 route (or whatever you did)?

There's one trail you can ride across the Mercantour legally and we rode the Bonnette as an alternative to get through an area that has no bike access. As far as I know the Queyras is OK for riding, it's the Ecrin and Mercantour that are mostly off limits. Some of the best trails we rode were in the Queyras area.

Couldn't put a figure on how much HAB but it was a lot, eg the carrys up to the Col Bonhomme or the Col Anterne, my saddle pad was a necessity -

DSCN9679 by james*o, on Flickr

I've got a load of route sections that are as-yet unlinked from/based on what we found on that ride and past trips in that area. The GR5 day 1-2 from Geneva isn't great anyway so I'd say overall it makes a good base for your own route rather than a good route in itself. So one rainy weekend I'll start GPXing and linking some of the routes from this C-D-S site and my own stuff to make a route for another ride in that area, still think it's the best ride I've done. Hard, but the riding was amazing.

The VTOPO books are highly recommended in general. I have several, and they've rarely let me down.

It was the Vanoise National Park I was thinking of in particular, but looking at the map again, the two short sections which the GR5 passes through are either HaB or easily bypassed on road.

Forgot about the Vanoise. Some of the GR5 in the Lac/Cornet Roseland area is HAB and not in a good way according to Chris E who rode it the year before we did. We dropped down the pass on road anyway as my friend had an injury then went up toward Les Arcs and La Plange, into the park there on some VTT trails and we cheeky-trailed a section of the park to get to the Col Palet. In late evening, no-trace bivi and out as the sun rose to ride down into Tignes. Saw other bikes in that area and we walked a section that was in use for cattle herding.

Did most of this last year with a few other peeps. Lovely route. Some nice technical sections and lots of opportunity for cafe stops.

jameso wrote:... cheeky-trailed a section of the park to get to the Col Palet...

On this route, mountain biking is apparently 'tolerated', althoguh the final section has a gradient of ~25% apparently:
https://www.utagawavtt.com/randonnee-vt ... Casse-4723
With what local knowledge I have (I know the Peisey-Nancroix ESF owner and his son) I'd prefer to get the lift up from Bourg, ride the fantastic trail down past the Refuge du Mont Pourri and then HaB up to Refuge du Palet. The trail from the Nancroix valley to the edge of the National Park is listed in the local VTopo guidebook as their 'V6' level, meaning 'you should consider a trials bike'