Martigny stands at the elbow of the Rhône, the place where the river turns from a westward run through the Valais to a northward one toward Lake Geneva, and it has been a crossroads since the Romans. They called it Octodurum, built a town, a temple and an amphitheatre here, and the road over the Great St Bernard, which starts at the edge of town, was one of the main routes over the Alps. You can still visit the amphitheatre, and a museum on the Roman site has a collection that is unusual for a town this size.
Today it is a bustling small city of about fifteen thousand people, with all the services of a larger place. There are fuel stations, bike shops, supermarkets, and a good choice of cafes and restaurants, plus a proper old town with wine bars where you can taste the local Valais wines. The Valais is Switzerland's largest wine region, and its white Fendant and red Dôle are often on the menu, along with raclette, the melted cheese scraped onto potatoes, which is the proper food of the region.
From here, a number of great roads begin. The road to the Great St Bernard climbs south to the Italian border at 2,469 metres, with the old hospice, famous for its dogs, at the top, and the road tunnel below it spares the winter traffic. To the west, the Col de la Forclaz leads to Chamonix and the Mont Blanc massif. Eastward, the Rhône valley road leads to Sion, Sierre and the vineyards of the Valais.
Martigny is warm in summer, protected by the mountains, and the valley can be hot and still, so start early. The Great St Bernard pass is open from about June to October. Fill up here, since the climb has few services, and check conditions before you go. The St Bernard dog kennel in town is an easy visit for a short break.