Old Mountain Line - Daan River Bridge Introduction
The Old Mountain Line's Daan River Bridge is located at the border between Taichung and Miaoli, adjacent to the south entrance of the No. 7 tunnel in Sanyi Township, Miaoli County, and the area of Houli District, Taichung City. It spans 637.39 meters and consists of 8 trusses made up of 10 spans of 62.41 meters each (one span between two piers is considered one unit). The Daan River Bridge was constructed in the 36th year of the Meiji era (1903) and completed in the 41st year of Meiji (1908), serving as an important bridge for transporting goods and connecting the north and south during the Japanese colonial period. The bridge was renovated after the Central Taiwan earthquake in the 10th year of the Showa era (1935). In the 52nd year of the Republic of China (1963), upgrades were made to enhance the bridge's structure so that it could accommodate heavier, faster, and more frequent trains. While it is not the original structure, it maintains a similar appearance to the initial construction, with minor differences in the trusses and connections. After the closure of the Old Mountain Line in the 87th year of the Republic of China (1998), no trains have operated on the Daan River Bridge. Currently, on the Old Mountain Line of Taiwan Railways, there are only three bridges with this type of steel truss structure: the Daan River Bridge (637.39 meters), the Dajia River Bridge (382.2 meters), and the Kaoping River Old Iron Bridge (1,526 meters). Due to the well-preserved condition of the Daan River Bridge, a digitization project for historical photos titled "Taiwan World Heritage Potential Site - Old Mountain Line" was carried out in the 93rd year of the Republic of China (2004). After reorganizing in the 99th year of the Republic of China (2010), it was paired with the return of steam trains on the Old Mountain Line. In the 105th year of the Republic of China (2016), the "Taiwan Old Mountain Line Railway Cultural Landscape Survey and Research and Preservation and Management Principles Project" was executed. The bridge is currently closed for management to ensure visitor safety.
