In general, allies are people or groups that have joined an alliance. When spelt with a capital A, Allies usually denotes the members of the alliances directed against the Central Powers in World War I and against the Axis powers in World War II.
... have closed platforms:
Charing Cross tube station (for the Jubilee Line)
Holborn tube station (for the Aldwych branch of the Piccadilly Line)
These stations ...