“Sewage covers usually reveal the date and the company that installed them," explained Nassar.Nassar stated that the oldest sewage cover in the exhibition dates back to 1914 as evidenced by the engraved Khedive flag of Egypt.
German Egyptologist Dietrich Raue, the head of the mission, said one inscription referred to Atum, an important and frequently mentioned god, as being responsible for the flooding of the Nile River in the Late Period between 664 and 332 BCE.
They are believed to be a middle-class family who probably lived during the Ptolemaic, early Roman or Byzantine period.
Mostafa Waziri, secretary-general of the Supreme Council of Antiquities, said: "We have not found names written in hieroglyphics".
The study, which began in 2016, took Nassar to a spiral of sinks all over Cairo.
These sinks vary in shapes and sizes but the most important aspect for a researcher is what is written or drawn on the covers.