The Hamburg-Altona link line (German: Hamburg-Altonaer Verbindungsbahn) is a railway line in Hamburg, Germany. It now connects the lines from the north and west of Hamburg and Altona station with Hamburg Hauptbahnhof and the lines to the south and east. It was initially designed as a freight line only but is it now one of the busiest lines in Germany. It includes the suburban tracks of the Hamburg Stadtbahn, originally the core of the Hamburg S-Bahn.