Go swim in the Lake Biel Bielersee (http://en.wikipedia.org/w...)
Take a look an stroll to the historic medieval town Altstadt.
Lake Promenade at the Strandboden.
Do a cruise on Lake Biel.
Go to the Taubenloch Canyon Taubenlochschlucht and explore the cascade.
Pick up a bike and take a ride around the lake or the jura mountains. If you can, take a look at the wineards: you´re going to find many medieval constructions and some good restaurants serving fish from the lake and local wine.
Drink a glass of the famous local wine especially white wine or local beer.
During ice-hockey season visit a game of the EHC Biel.
Visit the chocolate factory Camille Bloch at the City of Courtelary in the Jura mountains. 15 min from Biel/Bienne City centre
Visit the maschine-factory Mueum Müller. Tu-Su 14-17:00; Adults CHF. 8.- / Students CHF. 5.- (http://www.centremuller.c...)
August 1st is the national day of Switzerland, and watching the fireworks on a boat is a good experience.
In winter: Take the bus to Les Près d'Orvin and go sking and snowboarding 20 min from the city center
In the summer, there is a music festival at the old town.
