Tarpeian Rock

A steep cliff of the southern summit of the Capitoline Hill, overlooking the Roman Forum, the Tarpeian Rock (rupes Tarpeia) was used during the Roman Republic as an execution site. Murderers and traitors, if convicted by the quaestores parricidii, were flung from the cliff to their deaths. Victims of this punishment included:

Spurius Cassius, 485 BC
Marcus Manlius Capitolinus, 384 BC, for sedition
rebels from Tarentum, 212 BC
Simon Bar-Giora, 70 AD

About 500 BC, Lucius Tarquinius Superbus, the seventh king of the Roman Republic, levelled the top of the rock, removing the shrines built by the Sabines, and built a temple to Jupiter Capitolinus on the intermontium, the area between the two summits of the hill. The rock was also the site of a temple of Saturn, which contained the Roman treasury that Julius Caesar raided in 49 B.C.

The hill was later retaken by the Sabine king Titus Tatius. It is believed (see Grant, below) that at this time the Etruscan name Tarquinius was modified to the Sabine name Tarpeia. A legend then evolved to explain the conquest. According to this legend, the Vestal Virgin Tarpeia, daughter of Spurius Tarpeius, governor of the citadel on the Capitoline Hill, betrayed the Romans by opening the city gates to let in the Sabines in return for the promise of payment of 'what they bore on their arms.' Her anticipation was that she would receive their golden bracelets. Instead, the Sabines crushed her to death with their shields, and she was buried on the rock that was later named after her.

References

Michael Grant, Roman Myths, Scribner's, New York (1971), p. 123.