The ________ are a geologically old mountain range folded and deformed during the Paleozoic. The ________ are a geologically old mountain range folded and deformed during the Paleozoic. Appalachians in the eastern United States Rockies in the western United States Cascades in the northwestern United States Alps in Europe
These old mountains date back to 480 million years ago. These mountains were modified by plate collisions. The effects of plate collisions are still seen even today.