human
I'm going to the Grand Canyon soon and I need to know what I need to know about it. Can you help me out?
assistant
Sure! The Grand Canyon is a huge canyon in Arizona, United States. It's 277 miles long, up to 18 miles wide, and over a mile deep. It was formed by the Colorado River, which has carved through layers of rock for millions of years. There are many different points of view on how the canyon came to be, but one theory is that the river eroded away layers of rock, exposing the softer layers below. Over time, the river continued to erode these layers, creating the Grand Canyon we see today.