The Giza Pyramids, designed to last forever, have done exactly that. The massive tombs were built around 4,500 years ago and are remains of Egypt's Old Kingdom era. They are the largest pyramid complex in Africa. The kings of ancient Egypt built these monuments to preserve their own bodies and those of their people. Each new king had his own tomb constructed for him, using blocks of stone brought from as far away as Ethiopia. The Giza Pyramids were used again during the Middle Ages, when they were filled with sand to reach the required height. Today, tourists can climb inside the pyramids to see how the Egyptians lived more than 3,000 years ago. Or you can wander among the stones of the Giza Plateau with its beautiful gardens and museums. You don't need a tour guide to visit the Giza Pyramids; just arrive early in the site to find a spot to park your car. You can walk between the two biggest pyramids (the others are smaller) or take the elevator to the top of the Great Pyramid. To get an idea of the size of the Giza Pyramids compared to other monuments, place your hand flat against one side of the smallest one (the King Khafre).