Ongoing advances in information technology enable improvements in both the quality and topicality of data-based condition information of physical structures. The digital twin, a sensor-based method to simulate a physical structure, is a promising approach to achieve a preventive and even partly predictive maintenance strategy in the future. This paper provides a digital twin concept for the Filstal railway bridges in Germany. Because of its importance for the transport network, its complex structural components and thus extensive condition monitoring, the Filstal bridges are well suited for the usage of a digital twin. The concept includes the integration, processing and aggregation of data from bridge inspections and analytical structural safety verifications as well as monitoring and diagnostic examinations to continuously display the bridge condition. Although the example at hand will be realized for a railway bridge, the core approach can be used for other bridge structures as well.