Nile River Valley Wall Calendar: The Nile is the longest river in the world, approximately 4,000 miles from East Africa to the Mediterranean. The river valley contains awe-inspiring pyramids, grand temples, and colossal monuments that create an open museum, providing insight into past cultures. Take a yearlong journey to the most beautiful sites and artifacts of the Nile River Valley, including the Temple of Abu Simbel, the historic Pyramids of Cheops, and the Sphinx of Gizeh.