Stadsgarden

The Viking Line terminal in Stockholm is situated in the port called: Stadsgårdsterminalen.

There is a bus shuttle to the next subway station, but it is very expensive.
Walk (follow the coast line in western direction) like most other foot travelers do:
~ 10 minutes walk.

The subway station (tunnelbana) is called Slussen from where you have a direct connection to the main station:
T-Centralen
~ 4 minutes
Ticket: 1-zone (A)