The Bayon, a Cambodian temple

The Tullianum

The Tullianum was a prison in ancient Rome, located beneath the Comitium (large meeting space).

A circular chamber built of stone blocks, each layer projecting over the one beneath, the Tullianum was a conical structure described by Sallust (earliest known Roman historian with surviving works) as follows: "repulsive and terrible on account of neglect, dampness, and smell."

The only way in was via a hole in the ceiling. Jugurtha, King of Numidia, was tossed down the hole and later died of starvation.

The Tullianum wasn't a jail as we know it, but instead a place to store your captured enemy leaders until the time came to parade them around and let your citizens jeer at them. They lobbed a few other people down the hole too -- Christian martyrs, people who were going to testifying against defendants later on, that kind of thing.

‪Vercingetorix‬, who led the Gauls in revolt -- then surrendered to Caesar by taking off his armor and sitting at Caesar's feet -- spent a few years in the Tullianum before being brought up for the Walk of Shame ("Boo! Look at him! Boo! Hail Caesar!"). Then ‪Vercingetorix‬ went back down into the Tullianum and got strangled, which was a pretty standard method of execution.