Lahun pyramid, 4,000-year-old, has opened its doors to the public for the first time, displaying a network of passageways and an ancient burial chamber. A small team of archaeologists spent around a year clearing out the burial chamber inside the pyramid, which had been covered in rocks and debris since its discovery. The pyramid has been closed since its 19th-century discovery, but the Egyptian ministry of Antiquities decided to open it up as a tourist attraction.