There is nothing like wordless low-light cave exploration video to put me to sleep, so despite the 93 minute runtime this took a few attempts.
It’s certainly Frammartino-ish, re-enacting a 1961 spelunking expedition but without any explanatory dialogue, and giving equal weight to the kids playing ball and the solitary death of a shepherd on the surface. Lovely ending, the last explorer in camp drawing a map of the cave hears ghost echoes of the dead old man calling his animals as the fog rolls in.