Härkingen is a municipality in the district of Gäu in the canton of Solothurn in Switzerland.

The A1 is a motorway in Switzerland. It follows Switzerland's main east–west axis, from St. Margrethen in northeastern Switzerland's canton of St. Gallen through to Geneva in southwestern Switzerland. The motorway spans 383 km (240 mi). Besides the motorway's main route, it has several branches that are variously numbered A1a, A1h, A1l and A1.1. It was opened for the Swiss national exhibition of 1964.