The finest treks in the Alps share one trait: they change country along the way. The Tour du Mont Blanc (about 170 km, France, Italy, Switzerland) is the best known. The Alta Via 1 crosses the Italian Dolomites over roughly 120 km, refuge to refuge. The Via Alpina links Trieste to Monaco across 8 Alpine countries. At altitude, your connection is mostly about safety: weather, a shared position, an emergency call. A single eSIM follows you from one country to the next, Switzerland included.
Walking the Alps means crossing a border without noticing: a pass, a refuge, and you sleep in another country with another language on the menu. The three treks below embody that traverse, from the most accessible to the most outsized.
Here are their real numbers, the fitness to plan for, and the point too often overlooked in the mountains: keeping a reliable connection for the forecast, navigation and the alarm, even when you change phone zone at the top of a pass.
The Tour du Mont Blanc, king of Alpine treks
The Tour du Mont Blanc, or TMB, is the great loop around the massif. About 170 km and close to 10,000 m of ascent, across three countries: France, Italy and Switzerland. Most people close the loop in 7 to 11 days, usually anticlockwise, starting at Les Houches or Chamonix.
It clears around ten passes and runs from Chamonix to Courmayeur in Italy, then on to the Swiss valley of Champex, before returning to France. Each side has its own character: the Italian face offers the widest views of the massif, the Swiss part the gentlest pastures.
The TMB is not technical, but it is physical. My advice: book the refuges several months ahead for summer, since it is one of the busiest trails in Europe and beds go fast.
The Alta Via 1 in the Dolomites
The Alta Via 1 is the most accessible of the Dolomites high routes. About 120 km from Lake Braies to Belluno, with roughly 6,500 m of ascent, over 8 to 11 days refuge to refuge.
It stays entirely in Italy, but crosses Trentino-Alto Adige, a region with a double Italian and Germanic heritage, where you order your strudel as readily as your pasta. The scenery, vertical walls and limestone spires, ranks among the most spectacular in the Alps.
It is the ideal trek for a first big hut-to-hut trip at altitude: the refuges are comfortable, the stages well sized, and the waymarking clear. Book well ahead here too.
The Via Alpina, the full traverse
A change of scale. The Via Alpina is not a single trail but a network of close to 5,000 km, from Trieste to Monaco, spread over five main trails and 342 stages. It crosses the eight countries of the Alpine arc: France, Monaco, Italy, Switzerland, Liechtenstein, Germany, Austria and Slovenia.
Almost no one walks it in one go. You pick a section, often the Red Trail, the main axis linking the Adriatic to the Mediterranean. It is the trek for long traverses, for anyone who wants to live the Alps as a continent in their own right.
At this level, logistics become a journey of their own: several countries, several languages, several currencies, and a phone that changes network almost every day.
The three treks side by side
To place the effort and the number of countries crossed.
| Trek | Distance | Days | Countries |
|---|---|---|---|
| Tour du Mont Blanc | ≈ 170 km | 7-11 | France, Italy, Switzerland |
| Alta Via 1 | ≈ 120 km | 8-11 | Italy |
| Via Alpina | ≈ 5,000 km (network) | by section | 8 Alpine countries |
Switzerland, the border that changes the bill
In the Alps, the phone trap has a name: Switzerland. It has never been part of the EU roaming area. On an ordinary plan, data there is billed separately, sometimes at a steep rate.
The Tour du Mont Blanc is the perfect example. France and Italy apply EU roaming, but you pass through the Swiss valley of Champex for a day or two. Plenty of walkers do not even realise they have changed pricing zone at the moment they check tomorrow’s forecast.
Liechtenstein, crossed by the Via Alpina, is on the other hand inside EU roaming. So the real vigilance is about Switzerland, present on most of the great Alpine traverses.
Connected safety at altitude
In the mountains the phone is not a comfort, it is a safety tool. Three uses genuinely matter: checking the real-time forecast before an exposed pass, sharing your position with someone or with the refuge, and being able to raise the alarm if something goes wrong. The emergency number 112 works across Europe, but you still need a signal.
Coverage is good near refuges and resorts, weaker on the passes and in deep valleys. Always download your maps offline. For the rest, the worst situation is losing your data as you drop into a non-roaming country, just as a storm builds.
With a eSIM for Europe set up before departure, one eSIM covers the countries of the Alpine arc, Switzerland included. The phone switches to the right network on its own as you cross the passes, and you keep access to the forecast and the alarm the whole way. For the full map of where EU roaming ends, see One eSIM for all of Europe.
- For a first big traverse: the Tour du Mont Blanc or the Alta Via 1.
- Book the refuges several months ahead for summer.
- Switzerland is outside EU roaming, and it is on almost every great trek.
- Download maps offline and check the forecast before each pass.
- 112 is the shared emergency number across Europe.
- One eSIM covers the Alpine countries: no card to swap at the top of a pass.
With Orange, the service used by more than 300 million customers, you walk with a clear head: 200+ destinations covered, human support 24/7, and fully refunded if you never use your eSIM.
Ready to cross the Alps without ever losing the thread?
