Geocaching
Geocaching or "Geostash" its known as in INFRA. Is a game where you search for small canisters with a logbook inside, there you will sign date of discovery and username. (https://www.geocaching.com/play/search)
Origins
It was developer |Yucca| who added geocaches to INFRA according to Oskutin (Discord message link)
Other in-game mentions
Trivia
The model of the geocache in the game has the code GS8A7-- If you change it to real geocaching ID you will get GC8A7 which was an cache located in Sweden capital, Stockholm (Geocache GC8A7) (Yes the owner of the cache has been notified)
Geocaches are only allowed to be hidden in public areas. In INFRA most are hidden at non-public areas
INFRA model geocache