Complex sentence: A number of famous trains have been associated with King's Cross, such as the Flying Scotsman service to Edinburgh, and the Gresley A3 and later streamlined A4 Pacific steam locomotives, which handled express services from the 1930s until the early 1960s.
Split into simpler sentences: A number of famous trains have been associated with King's Cross, such as the Flying Scotsman service to Edinburgh. And the Gresley A3 and later streamlined A4 Pacific steam locomotives which handled express services from the 1930s until the early 1960s.