How difficult is the Tour du Mont Blanc?

The whole day's climbing is done in the first two hours. From Les Houches the route goes straight up on village lanes and then wide ski-area track, about 650 m to Col de Voza at 1653 m, where the rack line of the Tramway du Mont-Blanc is crossed. None of it is technical and none of it is interesting underfoot: hard, broad, mostly shadeless. Past the col the character changes completely, into a descending path through birch and spruce above the Bionnassay torrent, past the hamlet of Bionnassay and down to the floor of the Montjoie valley. From there to the end of the section it is low, undulating walking on forest tracks, farm lanes and short stretches of tarmac, threading hamlet after hamlet. It never settles into a rhythm and it is the least alpine ground on the circuit, but it is also the most populated, so nothing is far away. The section stops on the wooded rise just short of Les Contamines.

Navigation: Red and white GR blazes throughout and the line is obvious, but the pistes and service tracks around Le Prarion and Col de Voza cross each other repeatedly and the wrong track down is easy to take. The Col de Tricot variant leaves at the col: it is higher, steeper and longer, not a short cut.

In poor weather: Low and largely wooded, so rain here is an inconvenience rather than a problem. Cloud on Col de Voza costs the Bionnassay glacier view and little else. The Tricot variant, at 2120 m with a suspension bridge and a steep switchback descent, is a different proposition in bad weather.

Escape options: Easy the whole way. The Bellevue cable car and the Tramway du Mont-Blanc both serve the Col de Voza area, and from Bionnassay onward the route is rarely far from the Saint-Gervais to Les Contamines valley road, which carries a bus.

The one genuinely easy stretch on the French side. The trail runs through Les Contamines-Montjoie on pavement, then follows the Bon Nant upstream on flat gravel tracks and easy forest path to the baroque chapel at Notre-Dame de la Gorge, gaining barely 150 m in six kilometres. Shaded, level, and shared with day walkers, families and the leisure park at Le Pontet, so it is sociable rather than wild. It ends where the tarmac does. Everything past the chapel is climbing.

Navigation: Signed and unmistakable, on tarmac and broad gravel track the whole way up the valley.

In poor weather: Sheltered valley floor under trees. Rain means wet feet and nothing else, which makes this a sensible stretch to walk on a bad morning while the cols clear.

Escape options: The valley road runs alongside from the village to the car park at Notre-Dame de la Gorge, so there is no committing ground here at all.

The heart of the walk and the part that has to be respected: two frontier cols, 44 km and most of the circuit's serious ground. It opens on the Chemin Romain above Notre-Dame de la Gorge, a steep paved and slabbed climb through the gorge that is slick when wet, then eases onto pasture track past Nant Borrant and La Balme before the treeline is left behind for good. Above that it is open, stony ground to Col du Bonhomme at 2329 m and a further exposed traverse to the Croix du Bonhomme at about 2480 m, the highest point on the French side and where snow lies longest. The drop to Les Chapieux is grassy, long and hard on the legs. Tarmac up the Vallée des Glaciers gives an easy start to Col de la Seigne, a broad gradual climb with false summits that finishes on the Italian border. Past it the country changes: Val Veny is wide, bare and glacier-scoured, the path following the Miage moraine to Lac Combal before a strenuous pull onto the Mont Favre spur at around 2430 m. That buys several kilometres of near-level balcony traverse facing the Peuterey ridge and the Italian side of Mont Blanc, which is as good as walking gets on this circuit. It ends badly, on steep, loose, dusty ski pistes from Col Chécrouit down through Plan Chécrouit to Dolonne and Courmayeur.

Navigation: Waymarking is good, but above the treeline the ground hides it. The traverse between Col du Bonhomme and Col de la Croix du Bonhomme is where care is needed: it is exposed, the underlying path is covered when snow lies, and the descent line off the Croix towards Les Chapieux is the classic place to lose it in cloud. The Col des Fours variant, higher again, leaves at the Croix du Bonhomme. Below Col de la Seigne the paths through the upper Val Veny braid and rejoin, which looks like a navigation problem and is not.

In poor weather: The stretch weather actually governs. Snow lies on the Bonhomme cols into July in many years and it matters most on the exposed traverse between them, where the path vanishes under it; the Col des Fours variant holds it later still and can want crampons or spikes. Col de la Seigne sits on the watershed between France and Italy and takes weather off both sides. Lower down, the Roman road slabs above Notre-Dame de la Gorge are slippery in rain, and the ski-piste descent to Dolonne is dusty when dry and greasy when wet.

Escape options: The weak point of the circuit. From Notre-Dame de la Gorge there is nothing but the refuges at Nant Borrant and La Balme, plus whatever is staffed at the Croix du Bonhomme, for about 15 km and two cols until Les Chapieux, which has a road and a summer shuttle down to Bourg-Saint-Maurice. A road runs on to Ville des Glaciers, but past Refuge des Mottets you are committed again over Col de la Seigne, with Rifugio Elisabetta the only shelter before the Val Veny road head at Lac Combal, which has a summer shuttle to Courmayeur. Below Col Chécrouit the lifts take part of that loose descent off your knees, but only part of it in 2026. Courmayeur Mont Blanc Funivie's own summer list for 27 June to 30 August 2026 runs the Dolonne cabin lift, the Val Veny cable car and the Zerotta chairlift, and does not include the Maison Vieille chairlift, which is being taken out and replaced by a cabin lift for the following winter. So the two steep kilometres from Rifugio Maison Vieille down to Plan Chécrouit are walked whatever you do, and the ride only starts at Plan Chécrouit, dropping you at Dolonne a few minutes' walk from Courmayeur.

Two balconies and a border. From Courmayeur the trail climbs about 800 m through larch woods above Villair to Rifugio Bertone, a sustained forest pull with the treeline only at the top and a single viewpoint back over the town for relief. What follows is the easiest hard walking on the tour: a near-level traverse along the flank of Mont de la Saxe, high above the Val Ferret road, with the Grandes Jorasses filling the view opposite. It is open grass and stone with no shade and no shelter between Bertone and Rifugio Bonatti. The balcony runs out at the head of the valley at Arnouvaz, then a steady zigzag climb past Rifugio Elena on grassy hillside reaches the Grand Col Ferret at 2537 m, the trail's high point and the Swiss frontier. The Swiss side is gentler at once: pasture, the alp buildings at La Peule, then a long descent on tracks and lanes through Ferret into La Fouly. From there to Praz-de-Fort the walking is riverside and almost flat, wooden chalets and hay meadows, the quietest and least strenuous ground on the whole loop.

Navigation: Mostly simple: the balcony is a single obvious line and Swiss signposting on the far side is the clearest on the circuit. Two things to know. The Col Sapin and Tête de la Tronche variant leaves at Rifugio Bertone and is a fair-weather route rather than an alternative. In the Swiss Val Ferret the path between Prayon and Branche, at Treutsebo, has been rerouted onto the right bank of the Dranse de Ferret because of rockfall and the old line is closed, so follow the marking on the ground rather than an older track log.

In poor weather: The Val Ferret balcony faces south, sits above the treeline and has nothing to hide behind between Bertone and Bonatti, so it is hot in settled weather and a poor place to be caught by an afternoon storm. The Grand Col Ferret is a gap between two valleys and funnels wind. Low cloud costs the Grandes Jorasses, which is most of the point of the traverse. The Swiss valley below La Fouly is sheltered and walks perfectly well in rain.

Escape options: The Italian Val Ferret road runs below the balcony from Courmayeur to Arnouvaz, with steep connecting paths down from Bertone, Lavachey and Bonatti, so the first half is easy to leave. Arnouvaz is the last road before the col; the next is at Ferret on the Swiss side, roughly 11 km and 770 m of climbing away, with Rifugio Elena and the alp at La Peule the only shelter between. From Ferret the Swiss valley road and its postbus shadow the trail all the way to Praz-de-Fort.

Swiss forest and pasture, then back over the frontier and straight into the Aiguilles Rouges. A steady wooded climb from Issert to the lake at Champex ends the valley walking. Outside Champex the route forks, and the mapped line takes the Bovine route: a farm road to Plan de l'Au, then a steep, rooty, stream-crossed 45 minutes through the woods and about 650 m of climbing to the working alp at Bovine, where the cattle churn the ground and the view opens north to Martigny and the Rhône. It is not a col but it climbs like one. The descent to Col de la Forclaz through fields and woodland is gentle and quick. From Trient the section starts again from nothing: gravel track across meadow, then forty minutes of tight forest switchbacks and open hillside to Col de Balme at 2191 m, where the Chamonix valley and the whole north side of Mont Blanc appear at once. The mapped line then takes the crest of the Aiguillette des Posettes, rocky, narrow, increasingly uneven and completely exposed, before dropping in switchbacks to the valley road at Tré-le-Champ. The last kilometre climbs straight back out of the valley to the fixed ladders on the Aiguillette d'Argentière, a protected passage of metal ladders, handrails, platforms and steps broken by stretches of ordinary path. The route stays high above Argentière and does not enter it.

Navigation: Swiss signposting is the clearest and most comprehensive on the circuit, with walking times as well as directions. The fork that matters is just outside Champex, where the Fenêtre d'Arpette variant goes west up the Val d'Arpette and the main Bovine line goes southwest towards Champex d'en Bas; make that choice in the village, not at the sign. At Col de Balme the mapped crest route over the Aiguillette des Posettes separates from the older, lower path down to Le Tour. On the descent off the Posettes the crest gives out into several junctions below the treeline, all signed for Tré-le-Champ. Walkers who do not want the ladders leave the line at Tré-le-Champ for the Col des Montets variant.

In poor weather: The Bovine climb is the wet-weather half: forest soil and roots, and stream crossings that get awkward in heavy rain or early-season snowmelt, with a working alp at the top that is muddy in any conditions. Above Trient, Col de Balme holds névé into early summer and the crest of the Aiguillette des Posettes is exposed from end to end, so in wind or poor visibility the old path down to Le Tour is the sensible line. The ladders themselves are secured and less alarming than they sound, but wet metal and a queue on them slows the whole climb.

Escape options: Champex, Col de la Forclaz and Trient are all on roads with bus services, but the Bovine ground between them has none for about 14 km. Col de Balme has no road either: the quickest way off is the old path down to Le Tour and the Chamonix valley. From Tré-le-Champ the valley road, Montroc-le-Planet station on the Mont-Blanc Express and Argentière are all within a couple of kilometres, and this is the last easy exit before the ladders.

The Grand Balcon Sud, and the best sustained viewpoint on the circuit. From the cairn at La Tête aux Vents the path traverses southwest across the Aiguilles Rouges reserve at around 2000 m, dropping to the lift station at La Flégère and then rising and falling over rocky meadow, scree and boulder to Planpraz. It is stony the whole way, with ramps and stone steps where the ground steepens, and it walks slower than its modest height gain suggests. The slope faces south, straight across at the Chamonix Aiguilles and the Mont Blanc massif, which is the entire reason for being here. The trail stays high on the valley wall and does not go down into Chamonix or Les Praz, though lifts at both ends do. Expect company: this is a lift-served day walk as much as a stage of the TMB, and one of the better places on the route to see ibex and chamois.

Navigation: The junction at La Tête aux Vents, marked by a large cairn, is the one to get right: the path north climbs to the Lacs des Chéserys and Lac Blanc, the TMB turns southwest for La Flégère. After that the balcony is a single line across the hillside with a lift station at each end, and it is hard to lose.

In poor weather: Rock and scree the whole way, so it is slower and less secure after rain. The section's entire value is the view opposite, and low cloud removes all of it while leaving a stony traverse. South-facing and hot through the afternoon, with no shade to speak of.

Escape options: The easiest section on the circuit to leave. La Flégère has a cable car down to Les Praz and Planpraz a gondola down to Chamonix, roughly at the two ends of the traverse, and steep paths drop into the valley from both.

A last climb, then the biggest single descent on the circuit. The pull from Planpraz to Le Brévent at 2525 m finishes across a boulder field crossed on laid rock slabs. From the summit, with the whole massif directly opposite, the trail drops past Lac du Brévent to the Refuge de Bellachat and then falls roughly 1200 m down the flank of the Aiguillette du Brévent. That descent is the section: loose stone on steep ground, timber-reinforced steps, fixed metal handrails where the path is cut through rock, and one crossing of the Ravin des Vouillourds secured with a chain. It is continuous rather than technical, and it is quads and knees that pay for it. Below the Merlet junction the trail enters forest, skirts the Parc de Merlet and joins a paved access road, then drops on lanes and woodland path into Les Houches to close the loop. It stays on the west wall of the valley throughout and does not pass through Les Bossons.

Navigation: One obvious line from Planpraz over Le Brévent and down. Signs at Bellachat give Merlet and Les Houches, and the route follows the perimeter of the Parc de Merlet before joining its access road; below that there are several ways into the village and all of them work.

In poor weather: Le Brévent is high enough to hold névé into early summer and the summit boulder field is awkward where patches lie across it. Below Bellachat the descent is the issue: loose stone on steep ground, timber steps and rock-cut sections with handrails, all of it slower and less secure when wet. The chained crossing of the Ravin des Vouillourds is the one place to stop hurrying.

Escape options: The Brévent cable car at the summit is the last realistic exit. After it the descent is committing: about 1200 m of steep ground with the Refuge de Bellachat the only shelter, and the Merlet access road at around 1650 m the first place a vehicle can reach you, roughly two thirds of the way down.