Difficulty / Planning / Safety

Trekking the Tour du Mont Blanc in June – early season

June can seem to be the perfect time to trek the TMB. Trekkers hoping to avoid the crowds and enjoy alpine flowers in bloom are often drawn to trek during this early shoulder season before the holiday season kicks in good and proper.

When trekkers tell me they want to trek in June, most are surprised by my one word response. Snow.

Yes. There is invariably snow on the TMB during the last two weeks of June and often into the first week of July. Many people planning an early TMB trek do not realise this.

Snow can mean a totally different experience of the Tour du Mont Blanc. Trekking during this early season should be well thought through with realistic expectations.

Laura, one of my zoom clients, climbing the Col de la Croix du Bonhomme in June

Conditions trekking during this 3 week period are hard to predict. Snow levels are dependent on two things – the amount of snow that fell during Winter and two – the melt rate come Spring.

Consider this – Chamonix ski lifts are STILL open into the first week of May for end of season skiing – this puts into perspective how much snow is still up there in May and June.

Given that so many trekkers planning their trail don’t realise this – I thought it would be prudent to write a post about trekking the Tour du Mont Blanc in June so you can decide whether this is the TMB you envisaged, and if so, to help you plan with confidence.

Alex, one of my zoom clients, enjoying the snow on the TMB in June

So what is it like to trek the Tour du Mont Blanc early season?

There are still a large number of trekkers who hike the Tour du Mont Blanc in June but it is quieter than the peak months of July and August.

Chamonix mountain guides do go out on the trail before the opening date to clear sections where possible or put in ropes. The main trail is generally clear mid June however snow fields will still cover the cols (mountain passes) at 2000m plus.

Through the snow fields there will be a visible track for you to follow as others before you hard pack the snow into a route. You’ll follow deep foot tracks in the soft snow. This snow packed route over the high cols will change as the snow melts and the main path becomes again visible.

The two dangers that trekkers should be aware of hiking during this time are:

1/ slipping whilst traversing snow covered sections of the trail with high exposure

2/ melting snow bridges (that often have strong torrents underneath – not something you want to fall into)

What do we mean by high exposure? High exposure means one side of the trail descends very steeply – a slip could mean a long fall down.

There are particular sections of the trail that have exposure that are prone to hold onto the snow a little longer, for example right at the beginning of the traverse to the Col de la Croix du Bonhomme setting off from the top of the Col du Bonhomme (see the first two photos below). The third photo is a snow bridge over a torrent on the climb up to the Col du Bonhomme. The last photo shows the whole first traverse section towards the Col de la Croix du Bonhomme taken from the top of the Col du Bonhomme.

Snow filled gullies can also be tricky to cross where there’s a degree of exposure.

There’s a particular tricky one on the way to Col de la Seigne towards Refuge Mottets on stage 2 (first photo below). The ascent up to Refuge Elena from Hotel Chalet Val Ferret on stage 6 is prone to snow filled gullies early season! The second photo show one of these. Both taken mid June 2023.

The third photo is looking back onto the Contamines-Montjoie valley from the beginning of the ascent of the Col du Bonhomme – June 2023. The bottom photo is on stage 4 heading towards Refugio Maison Vieille mid July 2018.

Another thing to note in early season is there can be a fair degree of mud! Melting snow equals mud. Expect to squelch down some descents – this can make going downhill a bit trickier, more prone to slipping and possibly tweaking something so caution is wise.

Some trekkers choose to descend snowy descents by sliding either on their bums or standing up (with invisible skis) – a much more fun alternative.

What early TMB trekkers need to be aware of:

1/  that extra equipment should be taken to keep safe. Hiking crampons (with spikes not circular flat discs) are normally required. They don’t weigh a lot so there’s no excuse not to throw them into your bag. You will definitely feel safer with these on when crossing a snowy traverse with a lot of exposure! Mid June you may even want to consider renting a lightweight ice axe. You would hold this in one of your hands whilst crossing a tricky section – its the only thing that would stop you if you fell.

2/ you should definitely not be planning to take any of the variants (except from perhaps variant stage 1 via the Col du Tricot which is generally always clear) during this time. It’s too dangerous. If you are staying at Refuge Mottets you would need to descend down the traditional route via the hamlet of Les Chapieux.

3/ you should visit the High Mountain Office in Chamonix before setting off to find out about up to date conditions. If you are booking a self guided Tour du Mont Blanc trek then the company you have booked with should be telling you up to date conditions on the trail as well. If in doubt – ask. 

The High Mountain Office updates weather conditions here. Check this page regularly the week before your trek however there is no substitute for going in and speaking to them.

An example of the High Mountain Office TMB conditions update posted on their website on June 20th 2023

“Only the Col de Tricot can be safely negotiated. On the Col des Fours side, there is a lot of snow, the slopes to be crossed are long, steep and exposed and there are several dangerous torrent crossings (water flowing strongly under the snow with the risk of being swept away). It’s also too early to tackle the Arpette window”But there is still snow on the main passes: Col du Bonhomme – Col de la Seigne – Grand Col Ferret – Col de Balme. Crossing the Col du Brévent is still problematic (see above) and it is preferable to take the Brévent cable car back down to Bellachat or to go around the bottom (Planpraz- Plan Lachat – refuge de Bellachat- Les Houches).Snow-covered sections of the route require appropriate and essential equipment to minimise the risk of slipping: – high waterproof boots – poles – hiking crampons (and mountain feet!)

We did visit the Bureau des Guides in the Maison de la Montagne building. They were very helpful. We purchased a couple of maps from them too.

Corinne and Bill Barnes, Aug 2023
Snow bridges become more unstable as the weather warms. In this photo the snow bridge is quite obvious – in other places you cannot see the conditions underneath so caution is required crossing one at a time

So when does the TMB trail actually open?

The trail opens on 14th June every year but this is France – there are no rules – there are no physical barriers that are taken down on the 14th June and the trail ‘opens’. What it means essentially is that the infrastructure on the trail opens on the 14th, and whilst some of the public transport options won’t kick in for a few weeks, the refuges are now open and you’ll see trekkers on the trail. 

As mentioned above, the guides of Chamonix go out on the trail to clear tricky sections or to put in ropes if necessary before the 14th June. This does not mean it is ‘safe’. If snow is covering sections of the trail which have significant exposure (one side falling away very steeply) then trekkers need to use caution and extra equipment to safely cross (hiking crampons & possibly an ice axe) – as the High Mountain Office phrase it ‘to have mountain feet’!.

I want you to know the risks, what to do and what NOT to do.  Tragically a solo trekker perished in June this year on the Cols des Fours by falling through a snow bridge into glacial water. This variant should never be taken early season as the snow covers torrent crossings (glacial streams) which are fast flowing. Snow can completely blanket this water so trekkers are unaware of it. Accidents can happen as snow bridges begin to become unstable as the weather warms.

Lac Blanc is almost still completely covered by snow – photo taken on June 24th 2023. Stages 10 and 11 take some time for the snow fields to thaw. Expect to encounter snow early season at Lac Blanc and Col du Brévent.

Where are the tricky areas to be aware of hiking the Tour du Mont Blanc in June?

In general there are always the same tricky areas when trekking Tour du Mont Blanc in June.

These are (but not limited to):-

  • Flégère – expect Lac Blanc to have a lot of snow surrounding it with the lake appearing much smaller than normal as ice and snow cover it.
  • Brévent – there is always a lot of snow still on the Col du Brévent. The High Mountain Office will normally advise hikers to avoid this and take a lower route. If you were planning to hike stage 11 first (which we often suggest later in the season to help with accommodation planner – between stages 10 and 11 accommodation is limited) then don’t. It’s best to add stage 11 as its chronological stage to allow more snow melt by the time you come around to it 11 days later
  • Col du Bonhomme / Croix du Col du Bonhomme – whilst the Col du Bonhomme does not have any real exposure once you get to the top and start the traverse to the Croix du Col du Bonhomme – there is a lot of exposure to the right hand side – the mountain descends steeply to the right and the trail with snow on is a very narrow track where caution and concentration is necessary. See the photos further up in this post.
  • Col des Fours – this always holds a lot of snow until the beginning of July. There is a very steep descent from the top of the Col des Fours which can be tricky with snow on but a much bigger danger are the unstable snow bridges crossing the glacial torrents (see above)

In the one main snow section, I think my micro spikes, a crucial item and honestly unsafe without.  I did see a couple folks without, and think in the moment, each agreed they wish they had them.  It was super steep and side hill.  The snow was crusty early, but got soft rapidly in the sun.  Many of the folks I spoke with had no idea what a fall arrest was, let alone practiced in them.  That particular section just passed the Col Du Bonhomme, if someone slipped and wasn’t able to immediately arrest, they would be traveling far too fast and seemed everything looked to end in a vertical fall or large boulders.  Simply a prime example of where not to risk it.  Spikes in that section should be a mandatory safety item.

While I only wore my spikes twice, and only once for any real distance, I’d never go that time of year without them.  That said, the torrents are what personally unnerve me more than anything else.  When the rotting snow bridges start to give way, I take particular note.  I’m over 6 feet tall and not what one would consider petite, so when also carrying a heavy pack, I always imagine if a torrent is going to collapse with someone crossing it, I have a higher probability of being that someone.  There were a few that I personally found unpleasant to cross, and honestly the only remotely sketchy parts of my trek.  With spikes, the snow fields were actually quite enjoyable, even with the steep grades, but there isn’t really any safeguarding a torrent other than going around which at times isn’t an option.  I didn’t have any problem though, opting to take my time, and on a couple moving up slightly to clearly thicker snow that was less traveled, and therefore less rotten without the darker prints from previous hikers soaking up the sun’s warmth and growing softer in the mid-day.  

Will Walton, Alaska

If you have trekked the Tour du Mont Blanc early season, we would welcome your comments below to help other people planning their TMB to decide whether trekking in the second half of June or first week of July might be something they would consider.

As always, thank you.



No Comments

    Leave a Reply

    This site uses Akismet to reduce spam. Learn how your comment data is processed.