||As a special plant for train maintenance in northern Taiwan, the Taipei Railway Workshop was founded in 1885 and moved in 2011, reflecting the changes in Taiwan’s history, transportation, and industrial technology. Now, it is planned to change the maintenance plant into a railway museum in the form of an in situ site. This study briefly introduces the historical background and present situation of the Taipei Railway Workshop and takes its forging workshop as the object for investigation and exhibition planning. According to the preservation and maintenance methods of the cultural heritage of the museum, the investigation process proposed includes four steps: Site exploration, object registration, object research, and exhibition planning. The work area in the plant is divided into shaping and forging areas, as based on the categories of the machines on the site of the forging workshop. In this study, a total of 85 industrial relics in the forging workshop are registered for systematic research. The working conditions, including machine parts for train maintenance, manufacturing processes of parts, and the relationship between in-line on-site machines and tools, of the forging workshop before closing are restored, as based on the principles of machine manufacturing, literature, and retired workers’ oral histories. Finally, an in situ exhibition plan of the forging workshop is put forward based on the results of the object research.