Ossuaire is a pale city whose upper storeys never quite agree with its ground plan. Across its limestone plateau, narrow houses gather into thick, irregular blocks; walls step sideways, rooms bridge alleys, and small courts interrupt otherwise valuable frontage. These displacements follow burial rights beneath the pavement. A family may own a deep stratum extending under its neighbour while lacking permission to anchor a pier in the shallow graves directly below. Buildings make those disagreements visible: blind bearing walls, long relieving arches, and inhabited upper floors balanced over passages that must remain public.

The oldest lineage quarters grow around shafts through which successive generations are lowered into the bedrock. Their ordinary houses have rubble-limestone walls, limewashed interiors, shallow masonry vaults and roofs paved with thin stone flags. Heavy ground floors support fewer, smaller rooms above; open roof courts supply light without deep timber-framed openings. Shafts occupy little forecourts behind paired thresholds, with removable stone hatches and sufficient clearance for a bier. Shops face the street beside these entrances, so bread queues, children and burial processions continually negotiate the same few metres. A grave is part of the working household, not an excuse to make every façade a mausoleum.

Excavation supplies abundant rough stone, but sound long lintels and accurately fitted roof slabs demand expensive selection and labour. Wealth appears in broad openings, thin joints, carefully graded pale surfaces and the ability to leave ground unbuilt. Modest houses reuse short blocks beneath brick relieving arches; old inscriptions sometimes survive sideways in a jamb after an authorised clearance. Lime render protects friable stone and unifies piecemeal repairs. Warm ochre ceramic gutters, screens and roof tiles mark later additions, particularly where workshops can buy kiln products more cheaply than dressed masonry.

Carrion moths make exposed timber, leather and thatch a collective liability whenever burial fails. Doors are riveted metal over mineral-filled cores; shutters are pierced ceramic or folded sheet iron. Imported timber survives chiefly inside sealed, inspected rooms, an expensive pleasure that neighbours regard with suspicion. Working districts favour brick vaults on stout stone piers, washable lime finishes and replaceable metal screens. Newer construction uses costly iron beams and shallow tile vaults to cross protected ground without inserting foundations. Its flatter roofs and long, shaded galleries contrast with the compressed arches of inherited houses.

Burial depth is not a simple ladder of prestige. Mineral contact and local fissures alter decomposition: some shallow bands return to use quickly, while coveted deep chambers remain occupied far beyond prediction. Survey marks cut into door reveals record strata rather than household rank. Reopened plots leave plugged inspection holes, recut thresholds and bands of replacement masonry. Descendants dispute these alterations as intensely as boundary walls.

On the plateau’s edge, younger households pool interment rights beneath low terraces and shared courts; established lineages consolidate tall, buttressed compounds inland. Civic construction asserts continuity through broad stairs, deeply recessed arcades and exposed courses aligned with surveyed strata, but must preserve access to the dead just as a tenement does. Throughout Ossuaire, dark metal seams, pale load-bearing masses and deliberately empty passages reveal the same tension: every addition above ground depends on an absence that can be defended below it.