It's incredibly hard to properly gauge the fortress' distance, alone in the mostly cloudless sky and without proper reference point, but you soon realise that it's actually still a good distance away, and put your crew back to work, hoping to get an hour or more of work in before its passage. Even so, your men are noticeably distracted, and when the fortress finally gets close enough that you can distinguish the tiny figures of Illuminated mages on the bastions, all work ceases entirely. The fortress is massive, larger than any city in Moolyage, and it floats through the sky completely soundlessly. An inconceivable weight of hard stone flies slowly over your heads, casting your camp, the bridge, this entire segment of the Oscuros into shadow. You feel as though an incredible weight has left you when the shadow finishes its passage, and the fortress continues south-westward, oblivious to your tiny presences on the ground.