Urbex: map an exploration, and know how to get out
Updated October 3, 2026
Urban exploration draws people with what it shows: disused factories, shelters, vaulted cellars, old networks. Underground or deep inside a large building, it also raises a very practical problem: finding the way out. Lidark is an orientation aid for iPhone Pro that keeps a record of your route. It opens no doors for you, and it is not meant for entering where it is forbidden.
First, the frame: explore with permission
An abandoned place still belongs to someone, and many sites are dangerous: weakened floors, unmarked voids, bad air, asbestos, water. Entering without permission can make you liable and put your life at risk. Sensible explorations happen with the owner’s or manager’s agreement, on an organised visit, or in a structure open to the public.
Many heritage associations and local authorities run visits to places that are normally closed. It is the best way to discover a site safely, with someone who knows it. Lidark changes nothing about this: use it where you are allowed to be.
Why a map changes the exploration
Underground, GPS does not get through, and neither does the mobile network. Visual landmarks, meanwhile, all look alike: a concrete corridor, a junction of galleries, one more staircase. Groups that get lost rarely do so because of one big danger, but through a series of small choices nobody remembered: turn left, go down a level, cross a room, and suddenly you no longer know where you came from.
A plan drawn in real time replaces that memory. You see the path walked, your position and the direction of the exit, without depending on a signal.
What Lidark does during the visit
You start a survey at the entrance, then walk on, sweeping the walls with the iPhone. The LiDAR scanner measures surfaces, ARKit tracks your position, and the app builds everything locally.
- Live minimap: walls, walkable floor coloured by altitude, path and heading, with the distance to the entrance.
- Thread back: the real distance to walk along your path, not as the crow flies, and an arrow to the next stretch. When the path loops, Lidark offers a shortcut.
- Landmarks: junction, shaft, danger. Drop them in one tap and they stay visible on the minimap, the plan and the 3D view.
- Night vision: a moon button turns the whole screen red to protect your eyes in the dark.
Prepare your exit
An app does not replace preparation. Before going down or into an authorised site:
- Confirm the permission and the site rules, and tell someone your expected return time.
- Carry at least two light sources independent of the phone, and a power bank: Lidark’s tracking is visual and the torch uses power.
- Dress for it: helmet, proper footwear, gloves, a change of clothes depending on the site. Never go alone if the site is complex.
- Locate the exit before going deeper, and set a turn-back rule (battery, time, fatigue).
- Read how to find your way with no GPS or network and check your iPhone is compatible.
Document, then respect the place
Back on the surface, each survey stays available as a 2D plan, an altitude profile and, with Lidark Pro, a 3D view. PLY or OBJ export opens the model in MeshLab, CloudCompare or Blender, for an archive, a presentation or a comparison between two visits.
The golden rule of exploration stays the same: take nothing, damage nothing, leave nothing. A dated 3D model is precisely a way to keep the memory of a place without wearing it down.
Limits to know
The iPhone’s LiDAR reaches a few metres: it maps what is close, not a large hall in one go. A long smooth corridor, water or suspended dust can degrade tracking; Lidark records nothing while tracking is unreliable and warns you by vibration. Over long distances, drift is possible: the survey is indicative, not a certified topographic document. And Lidark replaces neither a guide, nor a rope, nor a prior reconnaissance.
Otherwise, the app works entirely offline, with no account, and your surveys never leave your device: see the privacy policy.