On the day the ferry capsized, "Herald of Free Enterprise" was working the route between Dover and the Belgian port of Zeebrugge. This was not her normal route and the linkspan at Zeebrugge had not been designed specifically for the "Spirit"-class vessels: she used a single deck, preventing the simultaneous loading of both E and G decks, and the ramp could not be raised high enough to reach E deck. To compensate for this, the vessel's bow ballast tanks were filled. The ship's natural trim was not restored after loading. Had "Herald of Free Enterprise" survived, she would have been modified to remove the need for this procedure.