I've searched for this movie off and on over the years. When I was a little kid, my dad was watching this and I only caught one scene. The movie seemed like an old classic, maybe made around the 60s?
In the scene, women walk in a trance-like state through a field and down some tunnels where slab-like platforms await. Still in trances, the women lay on the slabs and an alien probe lowered from the ceiling down towards their heads.
I got scared and stopped watching after that, but the scene has always haunted me. I tried to draw the scenes as I remembered them if that helps anyone visualize.
The memory has faded but I think the field they walk through seemed like a battlefield or something? It was kinda rugged and dismal. There might have also been some men trying to break one of the women out of her trance.
EDIT: I think this is a muddled kid memory of the 1953 Invaders from Mars. The tunnels, the probe, and the hill with the sandpit, dark trees and fence seemed familiar when I went back and watched. Thank you everyone for your suggestions!!