The Valley of Gwangi (1969)

Cowboys Battle Monsters in the Lost World of Forbidden Valley.

★ 7.1 G 1h 36m Science Fiction Western Adventure

A turn of the century wild west show struggling to make a living in Mexico comes into the possession of a tiny prehistoric horse. This leads to an expedition to the Forbidden Valley where they discover living dinosaurs. They capture one and take it back to be put on display, leading to inevitable mayhem.