The unfinished obelisk is the largest known ancient obelisk and is located in the northern region of the stone quarries of ancient Egypt in Aswan, Egypt. It was studied in detail by Reginald Engelbach in 1922. The obelisk and wider quarry were inscribed on the UNESCO World Heritage List in 1979 along with other examples of Upper Egyptian architecture, as part of the "Nubian Monuments from Abu Simbel to Philae".