Entry hall 409 was the central keystone chamber of the Fourth Century, an awe-inspiring vaulted nave eighty arm-lengths long and fifty arm-lengths wide. He was flanked by double aisles of huge eight-sided piers carved from jet-hard black rock.
Here, the sheer stone-built majesty of the First Epoch was displayed in its purest, plain power. There were no decorative friezes, no carved lotus blossoms, and no statues of emperors or scholars. The room was dedicated entirely to load-bearing building. Massive transverse ribs of dark stone arched across the ceiling like the spine bones of a mountain, meeting at massive keystones the size of hayricks, each pinned through the center with a four-inch bolt of cast glowing-bronze.
In the center of this titanic hall, resting directly upon the central keel plate of the Ark, stood the Stele of the Unfallen.
The stele was a massive stone slab of hardened black shale, twenty arm-lengths high and four arm-lengths thick, rising from an eight-sided stone base of dressed hard speckled rock. Its polished surface was engraved with the complete load-bearing cross-section of the Ark Nadir, carved at a scale of one to one hundred, showing every bulk-head, every ballast chamber. Every one of the ten thousand statue niches that lined the central keel.
