Linked up by railway? (3)
I believe the answer is:
met
'linked up' is the definition.
(I've seen this in another clue)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for met that I've seen before include "Came together, encountered" , "Made a connection" , "satisfied" , "Got together" , "London police (abbr) - New York Museum of Art (abbr)" .)