It's probably for a quest they were going to incorporate but they never got done, or it had problems with other quests. Just ignore it unless you ABSOLUTELY want to get in.

Melusine you know everything don't you? ;)

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Anyway. Anomen's quest isn't in the docks district, it's int the bridge district, and that's Saerk who he could kill, depending on how you handle it.

I don't know about the locked door, but I do know what you're all talking about. Just north of the Delryn Estate and south of the Government Building in the Government District is a locked door barred from the other side. It seems to serve no purpose. The best thing to do is to look at the stronghold quests on the UHS website, maybe that door has to do with one of them. I can tell you right now though:

The Paladin, Bard, Fighter, and Theif Quests have nothing to do with it.