Sierre is nicknamed City of the Sun (French: Cité du Soleil) for its average of 300 days of sunshine a year.

It is the last official French-speaking city in Valais before the French–German language border of the canton located at the forêt de Finges, a few kilometres after the town.

Archeological sites on the Gerunden hill have produced neolithic objects and grave goods (including a polished stone ax), Bronze Age weapons and jewelry, Early Iron Age objects, and Roman era inscriptions, jars, jewelry, and coins.

A soapstone pot from the Early Middle Ages and a gold signet ring with the name Graifarius from the 6th century have also been found.

Other sites on nearby hills and near the chapel of Saint-Ginier, the Château de Villa, the churches of Sainte-Croix, Grands-Prés, Muraz, Glarey and Bernunes have yielded up graves originating from the Bronze Age to the Carolingian era.

[4] During the Roman era it appears that there was no major population center, but rather several scattered groupings of separate, upper-class dwellings.

Other Roman ruins have been found near the Château de Villa, in the church of Sainte-Croix (small terraced bath), in Grands-Prés by Muraz another house and in Gerunden the remains of buttress reinforced masonry indicate that a public or government building once stood there.

During the early imperial period, the duumvir or mayor of the Civitas Vallensium, Caius Cominus Chiu, lived in Sierre.

In the late imperial period, the family of the senator of Vinelia Modestina also lived in the area.

[4] In 515 the estate at Sierre was given by the King of Burgundy Sigismund to the Abbey of Saint-Maurice to hold as a fief.

The castles were razed in the mid-14th century when the noble families stood with the Bishop in his war with the Zenden of the Upper Valais and Counts of Savoy.

As vassals of the Bishop, they had the right to assemble twice a year to regulate the management of the common lands and the affairs of the local police.

In the 14th and 15th centuries, this cooperative adopted a larger political role as they started to administer more of the daily affairs in the villages and acquired the right to appoint their own judges.

At the beginning of the 20th century, Sierre became economically important as aluminium smelting has been historically enabled by its access to hydroelectricity.

The nearby Raspille mountain stream is considered the dividing line between the French and German-speaking portions of Switzerland.

It consists of the city of Sierre, the villages of Granges, Noës and Muraz, and the hamlets and settlements of Gerunden, Plantzette, Vieux-Sierre, Bourg, Glarey, Borzuat, Zervettaz, Villa d'en Bas, d'en Haut, Sous Géronde, Cuchon, and Monderèche.

The hilly topography of the valley floor derives from a very large postglacial rock avalanche, which collapsed from a fractured scar high to the north.

[7] The coat of arms is depicted (uncolorised) in the Schalbetter map (printed in 1545 by Sebastian Münster, Basel).

The entire Sierre town and surrounding are part of the Inventory of Swiss Heritage Sites.

[15] Sierre is host to a local wine museum (Musée Valaisan de la Vigne et du Vin) and of a museum dedicated to the memory of Rainer Maria Rilke who lived there until his death and is buried in the nearby town of Raron.

Sierre is twinned with the towns of In the 2007 federal election the most popular party was the CVP which received 34.23% of the vote.

In the tertiary sector; 1,373 or 26.5% were in wholesale or retail sales or the repair of motor vehicles, 224 or 4.3% were in the movement and storage of goods, 401 or 7.8% were in a hotel or restaurant, 255 or 4.9% were in the information industry, 104 or 2.0% were the insurance or financial industry, 414 or 8.0% were technical professionals or scientists, 300 or 5.8% were in education and 1,194 or 23.1% were in health care.

[10] Sierre has a long history of winemaking and is home to the Rèze grape used to produce the sherry-style Swiss wine Vin des glaciers.

The wettest month is December during which time Sierre receives an average of 72 mm (2.8 in) of rain or snow.

The education system in the Canton of Valais allows young children to attend one year of non-obligatory Kindergarten.

All the lower and upper secondary students from Sierre attend their school in a neighboring municipality.