At Bingemma gap, along the Dwejra section of the Victoria Lines, there’s a tiny chapel dedicated to Our Lady of Itria with a Punic tomb underneath it, but if you look to the right of the chapel, there’s a path down to a network of rock cut tombs believed to date back to the Bronze Age but also reused in Punic times, by early Christians, and also as refuge for local farmers during WWII.
I’ve not as yet managed to find any evidence of the exact age of these tombs (the map clearly says prehistoric) but spent a very pleasant hour or so scrambling in and out of them in glorious sunshine.