You can use your student ID as a semester rail and bus ticket to go by train and bus for free on certain routes.
In general, the students' union (AStA) is responsible for the semester ticket, so you can have a look at their homepage to get to know more about the ticket and the routes.

Please note that our advisors do not have the authority or power to sign certificates of enrolment for students who have lost their student ID or have an attrited chip card. Additionally, certificates of matriculation are not a valid replacement for your semester rail ticket!

semester rail ticket student ID chip card semesterticket