In many places in Germany, bicycles are not only a form of recreation or sport, but also an essential method of transportation. It's common to see adults in business suits riding their bike through the city, perhaps with groceries in the basket behind their seat. Cyclists are generally permitted to ride on the street, even if no bike lane is marked.
Biking can help reduce your carbon footprint, while also being a great way of seeing the countryside, with various Web sites - also in English -offering route planners.