The Land that Time Forgot was one of my favorite movies when I was a kid... because DINOSAURS! But seriously, a WW-I German U-boat and early diesel-era technology vs. DINOSAURS, how more dieselpunk could you ask?
Loved it as a kid and I still love it today.
Only ages after first seeing it I realized the script was by Michael Moorcock.
A Great Flick! Love ERB's stories and all of those Lost World type tropes!
Recently saw a remake of this film. = The Land That Time Forgot Based in the Modern Era, but still had the U-Boat and the Dinosaurs! I guess they recognized a Great Idea that was too good to loose! LOL