The "inner Kerameikos" was the former "potter's quarter" of the city and the "outer Kerameikos" covers the cemetery and the also the "demosion sema" (a public burial monument) where Pericles delivered his funeral oration in 431 B.C.
A plague pit and approximately 1000 tombs from the 4th and 5th century BC were discovered during excavations for a subway station just outside the cemetery. Thucydides describes the panic caused by the plague, which struck Athens and Sparta in 430, lasting for two years, killing a third of the population. He wrote that bodies were abandoned in temples and streets, to be subsequently collected and hastily buried. The disease reappeared in the winter of 427 B.C. The Greek archaeologist Efi Baziotopoulou-Valavani, who excavated the site, has dated the grave to between 430 and 426 B.C.