You can rent a bike anytime from the Call-a-bike points that you can see around the town. It’s pretty cheap. There are two tariffs: comfort or basic plan. In the comfort plan you pay 3 €/year for one time, and then 1€ for each 30 min. In the basic plan for 2016, it is 9€/month or 49€/year, and it is free for every first 30 min and then 1€/30min.
You can check the current prices on Call-a-bike
How can I use it?
Firstly, you have to register via Call-a-bike web site or mobile apps.
You write the bike number that you can find on the side of the bike to the mobile app and it gives you a code.
You tap on this screen and enter the code. Then you should push the red button on the left side of the back tire to unlock it and you are free to go.
When you leave the bike there are two options: break or leave. If you’ll come back after a short period you choose “break”. If your ride is finished, you chose “leave” and lock the bike by sliding the red part on the right side of the back tire.