Classification of arch bridges in the network of Deutsche Bahn. The preservation and the idea of continued construction are elementary components of structures and must be given more consideration again. Especially the existing structures in the network of the German Railways (DB) and in particular railroad arch bridges can positively support the goal of continued use due to their enormous residual load capacity and already demonstrated service life. For a successful service life extension, however, it was necessary to classify the approximately 6000 arch bridges in order to ensure a uniform handling of these structural forms. By evaluating the southeast regional area, with the most arch bridges, and a defined sample quantity of other regions, the classification was carried out on the basis of plan material as well as rule assessments. A first categorization was achieved based on geometrical characteristics, concretely the relation of arch spacing f to the clear width L of the vault. Three typical f/L ratios with suitable value ranges are applicable to the complete network of the DB. In order to give further recommendations for the investigation in exposed areas of the vault structure and to derive targeted rehabilitation methods, the f/L groupings were linked with the damage types which were found in the respective components of the vault bridge. The maximum stresses could be justified for flat segmental arches up to circular arches on the basis of the support line in the arch.