The Great Wall of China to 20 centuries to build. (James Stuart Griffith)

Happy Earth Day! Earth Day started 43 years ago as a way to get people to think about conserving, or protecting, the Earth. But it’s also a great day to celebrate the very cool planet that we all share and to learn more about the interesting people, places and animals on it. With some help from a new book titled “Where on Earth?” KidsPost discovered a few interesting facts to help get you excited about the place that we all call home.

The Great Wall of China is a wall in China that was built by hand — that means no big bulldozers or trucks, as you would see today — over about 20 centuries. (One century is 100 years.) The wall is about 5,500 miles long. That’s farther than from Washington, D.C., to California and back again.

A building called Burj Khalifa (sounds like burjsh kah-LEE-fa) is in a city called Dubai (sounds like doo-BUY), which is in a country called the United Arab Emirates. At 2,717 feet high, it’s the tallest building in the world — almost five times as tall as the Washington Monument.

Today in Washington it’s about 60 degrees outside, but over the past 100 years, temperatures on the planet have ranged from a freezing-cold 128 degrees below zero in Antarctica to a super hot 134 degrees in California in 1913. (Can’t complain about 60 degrees now!)

The earliest humans were probably most worried about food and shelter, but that didn’t mean they didn’t have time for some of the finer things in life. About 100,000 years ago, people started wearing jewelry, and about 40,000 years ago, people started playing music. Music existed even before writing. (Tra la la la la!)

The new book “Where on Earth ?” has a lot of cool facts about the planet.

There are 7,000 languages spoken in the world. Cameroon, a country in Africa, is not much bigger than California, yet about 230 languages are spoken there.

At 128 miles per hour, the fastest roller coaster in the United States is called Kingda Ka, in New Jersey’s Six Flags Great Adventure. In China, on a roller coaster called Dinoconda, the seats move forward and backward as the roller coaster is going, making riders feel as though they are spinning in a circle. (Whee!)

More than 30,000 people a year go skydiving in New Zealand, jumping out of planes and falling at 125 miles per hour. (A car on a highway goes about 60 miles per hour.)

People in the United States watch about 28 hours of television a week. In Sweden, Finland and Norway — where many areas have long, cold winters — people watch only about 18 hours a week. So get outside, everyone! And enjoy the Earth today and every day!

Moira E. McLaughlin