I mentioned the history of Florence and Tuscany the other day in an 18th/19th century setting context, but there are other underknown and underused periods from the place. The Etruscans were a strange lot, made stranger by the fact that they were completely absorbed into and overlaid by the Romans, leaving not very much behind them but a glimpse of an ancient Italy that's much more 'barbaric'-feeling than Rome (because, y'know, Rome came along and set parameters for what all subsequent societies considered 'barbaric'). Some of their art was extraordinary – if you ever use a chimera in your game show your players this to give them a sense of its slink and heft.
They also – like any self-respecting civilization hoping to be repurposed by hurried DMs – had massive tomb complexes made up of strange, round tombs like cakes with garish insides that you can totally use in your own game with essentially no work, thanks to archaeologists and their drawings. Here they are at various scales – a single elaborate tomb, a complex, a bigger complex – ready to be populated. Their form and logic – the circles with odd-angled slices cut into them, the way the smaller ones dance round the bigger – are consistent but feel powerfully unusual.
What's in them? Um, up to you, duh. If you don't have a use for a good necropolis then get out of here. But since some archaeologists have done my work for me, here's some of my work for you, in the form of a d20 chart I used when my current party went poking around the mausoleums of a declining half-orc civilization. This isn't suitable for a major plot-relevant tomb, but it lets you find out what happens in smaller tombs, or in a crypt the party might mistakenly end up in looking for another one. Each time a party enters a new tomb complex (or just before, actually, since sometimes this chart generates traps), roll on this disturbance table and put the result wherever seems most appropriate – the entrance if it's a trap, the main chamber if it's a mummy, I guess, but switch it up if they're working their way through the entire graveyard -
(1-10 – Nothing)
11 – Deadfall trap, still active- 2d10 damage, DC10 to spot the prop, DC15 to disable
12 – Curse trap, DC15 to spot, DC18 to disable – casts fear.
13 – Curse trap, DC15 to spot, DC18 to disable – casts cloudkill.
14 – cave bear (wandered in, is sleeping)
15 – d4 skeletons
16 – 2d4 skeletons
17 – d4 skeletons, d4 zombies
18 – spectre
19 – d6 animated armour (defensive constructs, still functioning)
20 – Mummy
And if you're wondering about the Etruscans and mummies, here is something deeply awesome. Your campaign definitely needs a mummy wrapped in the only known lengthy text in an otherwise undeciphered language. It also needs Etruscan snake-demons.