Q:The South Australian Railways 400 class is a class of 4-8-2+2-8-4 steam locomotives built in the early 1950s. 400 class locomotives served mainly on the South Australian Railways' narrow gauge Broken Hill line from 1953 to 1963 when they were replaced by diesel locomotives. The 400 class was temporarily returned to service in 1969 while the diesel locomotives were converted to standard gauge. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Mean Of Transportation