- Olten is a city in the canton of Solothurn in Switzerland. It is located on the Aare River and has a population of approximately 18,500 people. Olten is known for its charming old town with historic buildings, including the Church of St. Martin and the town hall. The city is an important transport hub, with a major railway station connecting various parts of Switzerland. Olten also has a thriving cultural scene, with theaters, museums, and a vibrant nightlife. The surrounding area offers opportunities for outdoor activities such as hiking and cycling.