You enter the portal and begin a systematic sweep of the place. You move carefully and quietly, but before long you find that it's just you, the ravens, and a strong the wind in this ruin.
After a bit of exploration, you find a the south wall of this old place has been mostly obliterated. Looking out from the ruin you see you are far above the city and just north of it. You surmise you must be on the Isle of Wine; a tall, rocky island that overlooks the city from the sea just a few hundred meters to the north.
[ +- ] Map of the city, including the Isle of Wine
Laurent recalls that the island was once part of Iskandar's harbor defenses, but fiends destroyed the outpost built on its top during the infernal siege twenty years ago. Look around, you can see how this area might have been a garrison of sorts, or a watchtower. You find what must have been bedchambers and privies (probably officer quarters) as well as larger open areas (muster halls or a mess perhaps).
The rooms contain a few relics from its military past - a chair here, a desk there, a shattered mirror. But for the most part, it resembles more of a construction site than a military fort. There are crates of unopened building supplies and some partially-erected scaffolds, but for whatever reason, it is obvious that reconstruction never went past the initial stages.
Very curiously, when Berry pass by the shattered mirror he notices that he has casts no reflection. Both Tilma and Laurent cast reflections in it as normal.
Standing at the edge facing the city, you can't help but survey the destruction caused by the earthquake. From this vantage point, you see a strange but unmistakable pattern of destruction that follows certain lines. These fault lines clearly form a pentagram:
[ +- ] Pentagram Fault Lines