The+Grand+Canyon

[| ​] The Grand Canyon

||  ||   || The   Grand Canyon   was made by the cut of running water. The Colorado River flows through the canyon. Some people think the Colorado River was there to start with and that over the years it cut through the rock, and now it is still there. If you look in the canyon, you can see many layers of rock. Geologists believe these rocks are at least two billion years old, which is almost certainly true, but no one can be exact. About 500 million years ago, tiny sea creatures called trilobites lived in the sea. When they died, minerals from the ocean replaced their cells in their bodies. Then a long time after, the bodies petrified, they were fossils. There are no fossils at the bottom of the canyon, but near the top, you can find trilobites, and sometimes even footprints or so of reptiles. Hiking in the Grand Canyon is very different from any other hiking because of its dry climate. Rangers say you need at least three liters of water for going down the canyon per day (remember, this is per person). You need less water in the winter, but you have to watch for freezing cold, rain, sleet or snow. You shouldn't have bare skin and in the summer you should wear light clothes and a hat. You should hike in the coolest part of the day and rest in shade at mid-day. The weather is, well, very odd. In the middle of the canyon it gets very hot and dry. On the North Rim it is like the mountains. On the South Rim, it's a mixture of hotness and mountain-like. And canyon walls are pretty dry. Three bridges cross the river: The Navajo, (used for vehicles) and two suspension bridges. Until 1907, the only way to cross the river was by a ferry. Later on, E.D. Wolly made a trail from the North to South rim. In 1921, they built a swinging bridge. The Grand Canyon is located in the northwest of Arizona