The answer depends on what kind of experience you want to have. If you want to see some of the most iconic arches and rock formations in the USA, go to Arches National Park. This park is small and easy to visit. With many short hiking trails to choose from and unique places to photograph, Arches is a great park for families, photographers, and hikers.
Canyonlands is one of the most underrated parks in the USA. The Island in the Sky district is easy to visit, with its overlooks and hiking trails. But the real beauty and adventure of Canyonlands lies beyond the Island in the Sky mesa. Go hiking in the Needles, drive the White Rim Road, go rafting on the Colorado River, and explore the Maze in a 4×4.
Canyonlands is one of our favorite US national parks but you need at least three days to really explore this park and learn what it is all about.