Ideas alone will not open bronze doors, he told himself. Ideas alone will not keep a light lit below ground. He had spent most of his life believing understanding came first and everything else followed. In this place, understanding without tools was just another form of helplessness.

The annex finally appeared around a bend where the corridor widened into a half-sunken civic spur. A sign frame hung crooked over the entry. Most of the letters had peeled away, but enough remained to read CITY MEMORY DEPOT, and beneath it, in smaller print almost lost under mold stains: ANNEX B — TRANSPORT, CLIMATE, HOUSEHOLD LEARNING. The outer shutter had jammed halfway up years ago. Roots had worked in around its edges. Someone larger and stronger might have ducked under easily. Elias had to lower himself sideways, one arm reaching through first, then pull the rest of his body after it while his side gave a hot warning that brought his teeth together.

Inside, cool stale air wrapped around him. The room smelled of wet paper, old dust, and trapped plant rot. Green paint still clung to the walls in broad museum colors meant to calm school groups and tourists. Display cases stood in rows, some upright, some tipped, all filmed with age. Tall storage drawers lined the far side under hanging diagrams of flood barriers, seed banks, and emergency shelter plans. What should have been a cache of useful things had been arranged as a lesson. He saw that at once, and the sight of it made his jaw tighten.

A century ago, perhaps less, these had been tools for survival. Now they had labels.