What does this traffic sign indicate?

The traffic sign depicted indicates a mandatory cycle path. According to German traffic rules, this sign informs cyclists that they are required to use the designated cycle path for their safety and to ensure smooth traffic flow. Vehicles are generally not allowed to obstruct this path, and it helps create a segregated space for cyclists away from motorized traffic, enhancing safety for all road users. It's crucial for cyclists to adhere to this directive to promote safe riding practices on the roads.