Sion lies at the bottom of the Rhône valley in a landscape that feels almost Mediterranean despite its Swiss location. The valley is wide and flat-floored here, bordered by steep vineyard slopes and then by the high Alpine walls that rise above them; the city itself sits in brilliant sunshine for an improbable number of days per year, making it one of the driest and sunniest places in Switzerland. This combination of Alpine grandeur and almost southern light gives Sion a distinctive character among Swiss cities — it feels less buttoned-up, more exposed to its landscape.
The city's most dramatic feature is immediately visible: two steep hills rising directly from the valley floor, each topped by a substantial structure. Tourbillon Castle carries the ruins of a 13th-century episcopal castle, mostly unrestored, its towers and walls open to the sky. Valère, slightly lower, bears the Valère Basilica, a fortified church of the 11th to 15th centuries whose interior contains the world's oldest playable pipe organ, dating from around 1435. The organ is still played during summer concerts, and hearing medieval music in that setting — within a fortress-church on a rock above the vines — is an experience that Sion offers and nowhere else can. The old town below the hills retains its medieval street pattern, with the Sion Cathedral, the Majorie Castle, and the curious Tour des Sorciers all within easy walking distance. The Sion astronomical clock on the town hall tower marks the hours as it has for centuries.
Valais is Switzerland's largest wine-producing canton, and the vineyards on the slopes above Sion are among the most scenic in the country. The local varieties are worth seeking out: Fendant (Chasselas), the dry white that pairs naturally with raclette; Johannisberg (Silvaner), rounded and slightly floral; and the red Cornalin, a variety almost unique to Valais with a spicy, cherry-inflected character. Wine bars and tasting rooms are scattered through the old town. Outside the city, the Le Petit-Chasseur prehistoric site and the Lac du Mont d'Orge nature reserve are within easy reach. For skiing, Verbier and Crans-Montana are both within striking distance, making Sion a practical winter base as well as a summer destination.