As shown on the History Channel, "How the Earth Was Made: The Rockies" explores the geologic history of the Rocky Mountains through evidence from fossils, sedimentary rock, granite uplift, plate tectonics, erosion, volcanism, and glaciation. The video explains how marine fossils and ammonites show the region was once covered by an inland sea, how subduction and crustal compression lifted the mountains, and how fossil leaves help estimate that the early Rockies were once much taller. It also examines river erosion, basin fill, volcanic ash deposits, glacial striations, and the Rio Grande Rift to show how mountains are shaped, worn down, and may continue changing. Rich in Earth science vocabulary and geologic reasoning, this documentary aligns well with curricula on geology, plate tectonics, fossils, landforms, and evidence-based scientific investigation. Part of the "How the Earth Was Made" series.