I used up the boats from the boatyard in Almaria, then mistakenly went down the one-way tunnel to the Marauder's Hideout. Now I can't get back into the northern section of Avernum so I can get to Melchanion and finish the game. There doesn't seem to be a land route from the south to the north.
I tried going to Bargha, getting through Lord Farrar's audience hall, killing all his minions (I haven't killed him yet) and getting through the back door and the traps. But then I don't have the strength to open the door after the pylons. I've been given King Starrus' quest to contact Melchanion, but that doesn't seem to get me through this gate.
Thanks.