October 29, 2025
Dungeons & Data: Subway Edition
Mapping Underground Structures with 3D Scans
iPhone subway scan sparks ‘cool or creepy?’ map war
TLDR: A hobbyist 3D-scanned a subway concourse with an iPhone and fed a quick floor plan into OpenStreetMap. Comments split between accessibility cheerleaders and privacy/security skeptics, with bonus pyramid-tunnel jokes—spotlighting the bigger question: should everyday people crowd-map interiors, or is that helpful tech turning a little creepy?
An urban tinkerer used an iPhone 17 Pro’s laser sensor to 3D-scan a Toronto subway concourse in minutes, then turned it into a floor plan for OpenStreetMap, the public map anyone can edit. With free Scanniverse, they walked the station, grabbed rough dimensions, cleaned the model in Blender, and traced rooms, hallways, and elevators. Indoor maps exist in Apple and Google for malls; this DIY run shows regular riders can do it too. It’s not perfect—holes and missing bits—but “good enough” to help people find their way.
And the comments? Chaos, comedy, and a mini flame war. Fans call it urban archaeology and a win for accessibility: “map the elevators, not just coffee.” Privacy hawks say scanning strangers in a station is creepy, while security folks worry about posting interiors of public infrastructure. OSM veterans reignite the editor feud—easy iD vs clunky JOSM—while Apple skeptics swear a tape measure works fine. One thread dives into pyramid rumors, with jokes about “secret tunnels” and Dungeons & Dragons IRL. Crowd verdict: amazing idea—just don’t wave it in commuters’ faces.
Key Points
- •An iPhone 17 Pro with LIDAR and the Scanniverse app was used to 3D scan a subway station concourse in about five minutes.
- •The scan, though imperfect, provided dimensionally accurate data sufficient for interior mapping in OpenStreetMap.
- •The workflow included importing a USDZ scan into Blender, cleaning geometry, and rendering an orthographic image for tracing.
- •JOSM with the PicLayer plugin was used to align the rendered floor plan over satellite imagery; the iD editor lacked this capability.
- •Interior features (rooms, hallways, elevators) were traced and uploaded to OSM, with height data (2.5 m) added from the scan.