Cerveteri's medieval town centre, clustered around the Castello Ruspoli, is worth a brief walk before or after the necropolis. The castle, a compact fortification built over the ruins of the ancient Etruscan city, dominates the small piazza at the heart of town and now houses the National Archaeological Museum. The medieval streets around it — narrow, stone-paved, with archways connecting the blocks — are typical of small Lazio hill towns and pleasant to wander.
The main piazza, Piazza Santa Maria, has a few cafes and restaurants where you can eat before heading out to the archaeological site. The town is very small — a population of a few thousand in the historic centre — and does not make much of its Etruscan heritage beyond the museum and signs pointing to the necropolis. That unpretentiousness is part of its charm.