Long ago, Greek writers created a list of the seven wonders of the world. But that list only included the wonders the writers knew about - the wonders of Greece and the surrounding countries. The writers did not know about all the wonders to be found in other parts of the world. People from Asia probably began arriving in North America about 40,000 years ago. To get there, they walked on sheets of ice more that 2000 feet (612 meters) thick. Eventually, they built villages and cities. One of these settlements, called Vinland, was built at Jellyfish Cove 500 years before Christopher Columbus landed. Other ancient people built dwellings as big as modern apartment buildings. And still others built huge pyramids and a beautiful city with temples and palaces in the middle of a lake. What other ancient wonders does North America hold? To find out, get ready to explore high cliffs, flowing rivers, and islands both frozen and tropical.