Yeah, the difference is really stark. If we weren’t being awful I’d recommend folks check both out because our three major mountain ranges (in the northwest we have the cascades which are volcanic and just kinda near the Rockies) are all super cool.

The Appalachians are over a billion years old and gorgeous, largely covered in deciduous forests and range from bumfuck nowhere (great for campers and stuff like whitewater rafting) to abutting major cities in the east coast that tourists wanted to see anyways, like a day trip from New York City or not that long from Washington DC. Ultimately though yeah they’re very small mountains because of their age. If you’d like to visit them without coming to the US a bit of the Scottish Highlands are somewhat part of the same range

The Rocky Mountains were raised during the cenozoic and as such are really tall because they’re pretty young, but also have a ton of dinosaur fossils. They’re majestic purple mountains and home to a major city (Denver) located a mile above sea level. They’re also home to the famous Yellowstone National Park, where we’ve got geysers, extremophilic archea mats, and wild bison and bears. If you like geology or paleontology they’re a great range to check out. They also reach well into Canada for anyone interested in checking them out without visiting the US