Okay, back 20 years or so, I remember a TV show that was on in the US. I think it was in black and white, so it may have been a rerun. Perhaps it was a movie.
There were some people hiding in a cave or catacomb. I think that there were two groups of people there, or the one group had split into two in order to explore.
At one point, one or more of the people glanced outside to see if it was safe. There were two large lizards, dragons, or dinosaurs fighting outside, and it was determined that it was not save to exit.
At a certain point inside the cave or catacomb, there were dormant creatures? robots? in niches along the wall. One of the characters (perhaps a child?) expressed concern or fear that the creatures would animate and be dangerous. Another character (I think an adult) stated that they were safe at the moment, and that while the creatures would eventually awaken, they would only awaken when the time was right (certain preconditions had to be met, or perhaps a certain date or time had to be reached), and the time was not yet right for them to do so. I can’t remember if the creatures actually came alive during the episode or movie.
Some characters came upon a room, and found a heap of stones in the center that had been arranged in a certain pattern. I think it may have been in the shape of an arrow. This assured/comforted one of the characters somehow (maybe something about the pattern indicating that someone else had been through and had succeeded in finding something, indicating that they were not too far off?).
Land of the Lost wasn’t B&W, though. Any show 20 years ago would have to be a rerun if it was B&W. I don’t know exactly when the last B&W show to be produced aired, but I gotta think it would’ve been at least 15-20 years earlier still than that.
Are you sure you weren’t just watching on an old B&W set?
Wait a tick. I was agreeing with the others that it was “Land of the lost” but you reminded me that there was indeed an episode of Lost in space that almost fits, IIRC the heroes find later that it was a prison ship and evildoers from the galaxy where in suspended animation, guarded by non other that Robby from the “Forbidden Planet” movie (in a non talking role in the LIS show)
I think Mr. Smith as usual was the one that operated some control without permission and got the inmates loose.
Searching…
Ah ha!
Could it be that the OP is combining both shows? I would not be surprised as I have seen memories mix and match media things before.
Some of this sounds a little like the 1959 “Journey to the Center of the Earth.” But mostly not.
“Dino” battle: Yep. Eh, sorta. Actually an iguana made up to look like a dimetrodon, and “something else” (wiki says a painted Gila monster).
Heap of stones: Sorta. Count Sachnussem is buried under a heap of stones.
His ancestor Arne Sachnussem’s skeleton is shown pointing the way, though, and not a stone formation.
Also, it’s in color, and I don’t recall any dormant things in catacombs. Well, they do awaken a giant lizard that wants to eat them before they are propelled to the surface by a lava/magma flow.
BTW, I think Irwin Allen used dimetrodon vs. giant lizard footage once or twice, at least in one B/W ep of Voyage to the Bottom of the Sea, an ep which feature the ever-delicisous Vitina Marcus. Note the he had reused that footage from The Lost World (1960)