Zion National Park would be a must see on my list of to do's when I get to go to Las Vegas. It's located about 150 miles from Las Vegas in Utah but well worth the ride from what I've read.
This park is over 147,000 acres with some of the most beautiful colors you have ever seen. The terrain goes from desert to forest and the elevations are widely different from 3,700 feet to 8,726 feet above sea level. The river canyon running through the middle is known as the Narrows.
You can take the scenic route through the park or if you are more adventurous you can do some hiking and rock climbing as well. You must purchase a permit for overnight backpacking for $5.00.
The park entrance fee is $20 per vehicle or $10 per person.