This haunting, 12-hectare Etruscan necropolis is a veritable city of the dead, with streets, squares and terraces of tumuli (circular tombs cut into the earth and capped by turf). Some tombs, including the 6th-century-BC Tomba dei Rilievi, retain traces of painted reliefs, many of which illustrate endearingly domestic household items, as well as figures from the underworld.
Another interesting tomb is the 7th-century BC Tumulo Mengarelli, whose plain interior shows how the tombs were originally structured.
In total, there are reckoned to be around 2000 tombs spread across the site, which is vast and not well signposted, so allow yourselves at least two hours to explore it.
Note also that if you're planning to continue your Etruscan exploration at Tarquinia, you can buy a combined ticket that covers Tarquinia's museum and necropolis as well as Cerveteri's two Etruscan sites. Valid for seven days, it costs €15/8 (adult/reduced).