The most amazing of all sculptures, the Sphinx, was said to be carved from a single block of limestone. Some people believe that the Sphinx was built by Khafre around 2500 B.C. Most scientists and archaeologists believe that the date is wrong. The Sphinx stands 66 feet high and over 240 feet long. Time and weather have worn it away. The structure is heavily eroded by what can only be water. Nothing else. But when did it rain heavily in the Sahara desert? Much more than 4,000 years ago! It's been estimated that the last period of heavy precipitation happened over 8,000 years ago. The Sphinx shows signs of heavy, heavy rain and erosion. This means that it had to have been in the pouring rain for a very long time.