human
I've heard that the Grand Canyon has been a popular tourist attraction for years. Why?
assistant
The Grand Canyon is one of the most beautiful and awe-inspiring natural wonders in the world. It's also one of the most visited attractions in the United States, with more than 6 million people visiting each year. The Grand Canyon is located in Arizona, and it is 277 miles long, up to 18 miles wide, and over a mile deep in places. The canyon was formed by water erosion millions of years ago, and it is home to many species of plants and animals.