Seems legit ( ) -- ~$3m prize pool, it seems to have already started but the application page is still open. Open to members of the public; what could go wrong?
Complex underground settings present significant challenges for military and civilian first responders. The hazards vary drastically across domains that can degrade or change over time and are often too high-risk for personnel to enter.
The DARPA Subterranean or “SubT” Challenge seeks novel approaches to rapidly map, navigate, and search underground environments during time-sensitive combat operations or disaster response scenarios.