Seaside Railway is a small train ride in Seaside Junction (formerly Thomas Town) that passes by the Shark Experience attraction at Six Flags Discovery Kingdom. When it was called Thomas the Tank Engine in Thomas Town the train passed by Tidmouth Shed, Lake Hackenbeck, Hackenbeck Station in addition to the Shark Experience attraction. In 2011 the train was rethemed to fit in with Seaside Junction and all Thomas and Friends references were removed, but the train still has Thomas' whistle.
In the past, the train tracks continued north along the edge of Lake Chabot to the other side of the park. The ride was known as Shoreline Express during this time. The tracks were removed sometime between 2006 and 2007, during the addition of Tava's Jungleland and the park's name change from Marine World.