reading the signal…
Signals / Object / Mapped places
in Herne, NW·counted·36 all time
A deep vertical shaft descending underground, typically abandoned, fenced, or marked with warning signs.
Counted, not streamed: Mineshaft has no time series, so it is read as a footprint across places. All-time count by city.
Things that physically exist: street furniture, signs, buildings. All-time counts.