From the wording of Luther’s post, I’m interpreting this as "west, then north", as opposed to "directly north towards the visible portcullis". But if I’ve got this wrong, I’m happy to rewind - just let me know.
You continue west beyond the two storerooms to the corner section that turns to the north. Ahead, the passage continues north for 30’ before arriving at a T-junction.
Looking to your right (east), you see yet another portcullis, just 10’ away.
To your left (west), 30’ away, you can see a large pair of double doors in the southern wall. Directly opposite these, in the northern wall, you see a side passage leading north. The westerly passage continues beyond these two features into darkness.
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Day 3, 9:30 am
Fenwick, Elf 1: 5/5
Gabbro, Elf 1: 4/7
Jessica, Cleric 1: 5/5
Luther, Cleric 1: 5/5 (Lantern)
Pickles, Halfling 1: 4/4
Ricard, Fighter 2: 12/14
Link to Gabbro's mega-maps ...