Archaeological heritage items, and why they are a question about digging

146 of the 1,108 Australian suburbs published on this site carry at least one archaeological heritage item. That is a count of our own published pages, not of every suburb in the country — the corpus grows, and this page is rebuilt with it. Between them they hold 563 mapped features. The distinction from the other categories is worth stating plainly, because a single question put to a conveyancer — is this property heritage listed? — will usually be answered against the item register and will usually come back clear.

An archaeological item is a statement about the ground. It is assessed on what a proposal disturbs rather than on how the result looks, so the matters it governs are excavation depth, footprint, service trenching, and anything that cuts a level platform. A proposal that alters no elevation at all — a pool, a basement, a driveway regrade, an in-ground tank — can engage it fully, while a substantial rebuild on existing footings may barely touch it.

That inverts the usual sequence. On an item or an area the heritage conversation shapes a design and is best had with a designer. On an archaeological record the relevant decision is made earlier and by someone else: how much the project digs, and where. Settling the excavation extent before drawings are commissioned is what keeps the finding cheap, and discovering it at lodgement is what makes it expensive.

Two practical notes. The records are concentrated in New South Wales in this dataset, because that state publishes the category as a distinct overlay rather than folding it into a general item register — so an absence on a page for another state is a statement about the published layer, not about the ground. And where a suburb carries both an archaeological record and acid sulfate soils, the two respond to the same decision: one excavation plan answers both, and they are cheaper to resolve together than in sequence.