An annual tribute to the history of locomotives. Get a glimpse of days gone by through an exhibition of train equipment and historic rail cars. Hear how railroads are currently used and plans for their future. Train lovers can also participate in transportation-inspired activities and enjoy musical entertainment. Metro Transit offers free rides to Union Depot throughout the event. 10 a.m.-5 p.m. Sat. Free. Metro Transit passes can be downloaded from the Union Depot website. Union Depot, 214 E. 4th St., St. Paul. 651-202-2700. uniondepot.org.