3.1 · Survey a Cave

A Cave Trip, Start to Finish

One trip, every step, from the car and back.

At the car: Ready the phone while you're still outdoors.

Check your settings once, then they stay set: units, scan quality, workout type and compass. Calibrate the compass outdoors (see Calibration). Make a project for the trip, start a hiking workout and a Hike Line for the approach.

At the entrance: Ties the cave survey to the real world.

End the Hike Line and the hiking workout. Start the caving workout, lock the entrance GPS and true north (State C), and lock the datum. Mark the datum with a scrap of flagging tape your crew can tie in to; take it with you when you leave. No tape behind.

Underground: Surveying the passage, crawls included.

Start a Cave Line and walk the passage. Drop stations, scans, photos, video and notes as you go, and add splays for passage shape. Crawls ahead? Put the phone away with Stow Mode and keep recording. The screen stays on while you survey; press the side button to lock and stow the phone.

Mid-trip: Useful between lines, and if the app closes.

Between lines, with the entrance GPS locked (with or without north), the cave screen becomes the Navigator: your live position against every line tied to the entrance, with Snap at a station when it drifts. You can review the map, stations and scans without stopping the line, and share with your team over AirDrop right there in the cave. If SpeleoMap closes in the cave, start a new workout and use Inherit calibration at a station from before (Cave Line).

Leaving: Wrap up the trip cleanly.

Tap End Survey at the entrance. Everything saves to the project and the Apple Health workout closes. Start a new Hike Line for the walk out.