Sion is the capital of VALAIS, a city of about 35,000 in the Rhone valley, with two rocky hills rising from the middle of it, each crowned by a castle. It has been inhabited for something like 7,000 years, which makes it one of the oldest continuously occupied sites in Europe.
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The climate is the thing that surprises people. The Valais is the DRIEST AND SUNNIEST CANTON IN SWITZERLAND, sheltered from Atlantic weather by the Bernese Alps on one side and the Pennine Alps on the other, with around 2,100 hours of sunshine a year and so little rain that the valley has been irrigated for centuries by hand-cut channels. This is not alpine Switzerland as the brochures sell it.
What Is Here
VALERE AND TOURBILLON ARE THE TWO HILLS AND THEY ARE DIFFERENT IN KIND. Tourbillon, in the frame at the top of this post, is a ruined fourteenth century bishop's castle burned in 1788 and left as a shell, and the climb to it is steep and the view is the reward. VALERE is a fortified church and is the one to prioritise: it holds the OLDEST PLAYABLE ORGAN IN THE WORLD, built around 1430 and still used for a summer festival of concerts.
The old town between them is compact, with the cathedral, the town hall and a network of lanes, and it is walkable in an hour.
VALAIS WINE IS A SERIOUS BUSINESS AND SION IS ITS CAPITAL. This is the largest wine canton in Switzerland, the terraced vineyards run up both sides of the valley, and the grapes include varieties grown essentially nowhere else: Petite Arvine, Amigne, Cornalin, Humagne. Very little of it leaves the country, which is the argument for drinking it here.
THE BISSES ARE THE VALAIS'S OWN WALKING. They are irrigation channels, some medieval, cut along the valley sides to bring glacier water to the dry slopes, with maintenance paths running beside them. Walking a bisse is nearly level, follows running water, and gives a view down the whole valley; the BISSE DE CLAVAU above Sion runs through the vineyards and is the obvious one.
Sion is also the gateway to the side valleys, with VAL D'HERENS, the Derborence and the Crans-Montana terrace all within an hour.
When to Go
September and October are the best months: the grape harvest, warm dry weather and the bisses still open.
April to June gives the valley green, the orchards in blossom and the walking at its most comfortable.
July and August are hot, and the Valais in a heatwave is genuinely hot rather than Swiss-mild, with the old town and the castle climbs exposed.
Winter is mild, dry and often sunny in the valley while the resorts above have snow, which is the advantage of basing in Sion for a ski trip rather than in a resort.
Getting There
By train, Sion is on the main Rhone valley line: Geneva about an hour and three quarters, Lausanne an hour, Bern about two via the Lotschberg. The station is a short walk from the old town.
By car, the A9. Three Swiss road facts matter more than the general advice. A VIGNETTE is required to use the motorways, bought at most border crossings, petrol stations and post offices or online, and driving without one risks a large fine. ROADS OUTSIDE URBAN AREAS ARE NARROW AND WINDING and the FCDO warns that conditions DETERIORATE FAST EVEN IN SUMMER, especially in heavy rain and in snowfall at altitude, so winter tyres and snow chains are the norm rather than a precaution. And traffic police ENFORCE STRICTLY, with any serious breach risking heavy fines or imprisonment. If you are in an accident, the orange emergency telephones along the roads are the way to call for help.
By air, Geneva is the practical airport at under two hours by train.
The side valleys and the ski resorts above are served by postbus from the station.
Is Sion Safe for Women?
Sion is a calm, prosperous Swiss cantonal capital. The FCDO publishes NO ADVISED-AGAINST AREAS ANYWHERE IN SWITZERLAND and the country has no regional-risks page at all, which answers the question most people are really asking. The advisory was last updated on 11 AUGUST 2026 and the change was to the European Entry/Exit System rather than to anything on the ground. On terrorism it uses the weaker of its two formulas, that attacks CANNOT BE RULED OUT, rather than the likely-to-try wording it applies to Austria and Sweden. What the page does carry is almost entirely about the mountains and the roads, which is the right emphasis for a country where the hazards are environmental rather than criminal.
The FCDO records a LOW RATE OF SERIOUS CRIME in Switzerland and then names where the petty crime is, which is more useful than a general warning: INCREASED REPORTS OF PETTY THEFT ESPECIALLY IN LARGER CITIES, AT GENEVA AIRPORT AND ON TRAINS TO AND FROM GENEVA. Elsewhere it is the ordinary advice to be alert at airports, railway stations and in crowds and not to leave valuables unattended.
THE HEAT IS THE UNDERRATED HAZARD HERE and it is the opposite of what people pack for in Switzerland. The Valais is the driest and sunniest canton, the two castle climbs are steep and unshaded rock, and the old town is stone. Summer afternoons here are a genuine heat problem rather than a Swiss inconvenience.
The castle paths are steep, uneven and polished, particularly the Tourbillon climb, and they ice in winter.
The bisses are level and exposed. Some run along steep valley sides with drops beside the channel, and the historic sections can be narrow with intermittent fencing. They are walking routes rather than mountain ones but the exposure is real.
There is a heightened risk of wildfires in summer, especially after drought, and the Swiss version carries a hazard most countries' does not: FIRES IN MOUNTAINOUS AREAS CAN LEAD TO ROCKFALLS. Check the bans on open fires for the area you are visiting, use only designated concrete-based barbecue areas and douse the coals, and note that CAUSING A FOREST FIRE WHERE THERE IS A BAN IS ILLEGAL EVEN IF UNINTENTIONAL and can bring a fine of up to 20,000 Swiss francs.
That last paragraph matters more in the Valais than almost anywhere in Switzerland, because this is the canton's dry side.
The Sion Packing List
The driest, sunniest corner of Switzerland, with two steep rock climbs in the middle of the city.
Our merino base layers are 100% Australian merino at 17.5 micron, and a long sleeve merino wool base layer for women earns its place here for the reason most people associate with the opposite climate: fine merino is a hot weather fabric that moves moisture and does not hold odour, so one top covers several days of a dry Valais summer, and a long sleeve keeps the sun off on an unshaded castle climb and a vineyard bisse. A heavyweight merino base layer from November to March, or if you are heading up to the resorts above.
Over it, very little in summer, and a Marmot PreCip Eco rain jacket for the shoulder seasons, though the Valais sees less rain than anywhere else in the country.
Merrell Moab 3 waterproof hiking boots with Darn Tough merino socks for the bisses and the castle paths, which are loose stone and polished rock rather than city surfaces.
Kahtoola MICROspikes from December to February for the Tourbillon climb, which ices and is steep enough to matter.
Not linked and worth packing: A SUN HAT AND HIGH FACTOR SUNCREAM, which in the sunniest canton in Switzerland are genuinely the first items; SUNGLASSES; A LARGE REFILLABLE BOTTLE, because the castle climbs have no water and the heat is real; a LIGHT SCARF for the cathedral and Valere; and SWISS FRANCS, though cards work everywhere.
Recommended Tours and Experiences
Essential Resources for Women in Sion
Emergency numbers: 112 works everywhere in Switzerland and routes you to the service you need, and the country also runs direct numbers that are sometimes quicker: 117 for police, 118 for fire and 144 for an ambulance. THE ONE TO SAVE BEFORE YOU GO INTO THE MOUNTAINS IS 1414, REGA, the Swiss Air-Rescue service, which is the helicopter operator for alpine emergencies and is reachable from anywhere in the country. The FCDO's own instruction for a medical emergency is to dial 112 or 144 and ask for an ambulance, and to contact your insurer quickly if you are referred on for treatment.
THE VALAIS IS THE DRIEST AND SUNNIEST CANTON IN SWITZERLAND, with around 2,100 hours of sunshine a year, and heat is the underrated hazard here rather than cold. Both castle climbs are steep, unshaded rock with no water on them. VALERE HOLDS THE OLDEST PLAYABLE ORGAN IN THE WORLD, built around 1430, with a summer concert festival worth timing a visit around. The bisses are level irrigation paths but some run along steep valley sides with drops and intermittent fencing. WILDFIRE RISK IS HEIGHTENED IN SUMMER in this canton particularly, and causing a fire where there is a ban is illegal even unintentionally. REGA air rescue is 1414.
US State Department travel advisory: the Switzerland advisory. Read the current level there directly rather than relying on a figure printed in any guide.
UK FCDO travel advice: gov.uk/foreign-travel-advice/switzerland, and read the safety and security page rather than only the landing page, because that is where the substance sits.
Main hospital: the Hopital du Valais in Sion is the cantonal hospital with a full emergency department and is the regional referral centre for the whole Valais, including the mountain accidents from the resorts above, so this is a well-covered destination. REGA air rescue is 1414. Switzerland is NOT in the European Union and IS in the EEA for these purposes, and a UK Global Health Insurance Card or an EU European Health Insurance Card does give you state-provided medically necessary care on the same terms as a resident. That is not the same as free and it does not cover repatriation, a private clinic or MOUNTAIN RESCUE, which is the gap that matters here and is why the insurance paragraph above is not boilerplate. Swiss healthcare is excellent and expensive in equal measure. TICKS ARE A REAL CONSIDERATION rather than a footnote: the FCDO names biting insects and ticks ESPECIALLY BETWEEN APRIL AND OCTOBER and names TICK-BORNE ENCEPHALITIS, for which a vaccine exists and is worth discussing with a travel clinic at least 8 weeks ahead if you plan to walk in forest or long grass. ALTITUDE SICKNESS is named as a risk in the ski and hiking areas, and the advisory lists them by name, including Engelberg-Titlis, Saas-Fee, St Moritz, Corvatsch and the Matterhorn.
Official health authority: the Swiss Federal Office of Public Health. covers the Valais cantonal hospital network
US Embassy: the United States Embassy in Bern.
Official tourism authority: Switzerland Tourism. publishes the Valere and Tourbillon opening arrangements, the bisse route information and the Valais wine trails
Takeaways
Prioritise Valere over Tourbillon. A fortified church with the world's oldest playable organ.
Walk a bisse. Level, beside running water, with the whole valley below.
Pack for sun, not snow. The driest and sunniest canton in Switzerland.
Drink the local grapes. Petite Arvine and Cornalin barely leave the country.
Solo women safety assessment: Sion is a calm, prosperous cantonal capital and an easy place to travel alone, with a compact walkable old town, a station on the main Rhone valley line, postbuses to every side valley and a woman alone attracting no attention at all. THE FCDO PUBLISHES NO ADVISED-AGAINST AREAS ANYWHERE IN SWITZERLAND and there is no regional-risks page; it records a LOW RATE OF SERIOUS CRIME and names the petty theft it sees in larger cities, at Geneva airport and on trains to and from Geneva, which is the line that bears on your arrival here rather than on the city. On terrorism it uses the weaker formula, that attacks cannot be ruled out. THE HAZARD PEOPLE DO NOT PACK FOR IN SWITZERLAND IS HEAT, and the Valais is where it applies: this is the driest and sunniest canton, sheltered from Atlantic weather on both sides, with around 2,100 hours of sun a year, and both castle climbs are steep unshaded rock with no water on them. A summer afternoon here is a genuine heat problem. THE SECOND IS THE GROUND: the Tourbillon path in particular is steep, uneven and polished, and it ices in winter. THE THIRD IS THE BISSES, which are level irrigation paths and therefore feel undemanding, while some of the historic sections run along steep valley sides with drops beside the channel and only intermittent fencing. THE FCDO'S WILDFIRE WARNING APPLIES HERE MORE THAN ALMOST ANYWHERE IN SWITZERLAND, because this is the dry canton: it notes a heightened summer risk especially after drought, that fires in mountainous areas can cause ROCKFALLS, and that causing a forest fire where there is a ban is illegal EVEN IF UNINTENTIONAL, with fines up to 20,000 francs. Check the open-fire bans before any barbecue.
Reading On
Sion is the Valais capital and the canton runs east and west from it. The Crans-Montana packing list covers the terrace resort above, and the Zermatt packing list and Aletsch packing list the Matterhorn and the glacier further up the Rhone. West, the Montreux packing list, Lausanne packing list and Geneva packing list cover Lake Geneva. North through the tunnel, the Kandersteg packing list, Oeschinensee packing list, Spiez packing list and Thun packing list cover the Bernese Oberland, with the Bern packing list for the capital. East, the Lucerne packing list, Engelberg packing list, Pilatus packing list and Rigi packing list cover the central lakes. For the country the Switzerland travel guide for women and the Switzerland packing list carry the transport, the advisory and the practical material in full. For why wool belongs in a hot dry valley, read the guide to merino wool base layers for women. Every destination we cover is indexed at the travel packing guide for women, and the base layers are at the Roman Trail collection.
If the outer journey is calling you, the inner one usually is too. Explore SoulMap at romantrail.com/blogs/soulmap.
