While conditions were often brutal for the poorest Romans convicted of a crime, the wealthiest citizens were rarely imprisoned. Instead, they were often put under house arrest while they awaited trial. Plus, voluntary exile was a much more available option to prominent aristocrats. It might sound like an obvious choice to take exile over execution, but exile came with its own dangers and hardships — even the most powerful lost their citizenship and all immovable wealth. Even worse, if they made the idiotic decision to return to Rome, any citizen was free to murder them on sight.

By the first century A.D., two main types of exile for upper class citizens had been established, according to Fergus Millar in “Condemnation to Hard Labour in the Roman Empire, from the Julio-Claudians to Constantine.” While during the Republic, wealthy Romans were only forced to stay away from certain places — most often the city of Rome and its surroundings — a newer, harsher form of exile later emerged. Deportatio forced citizens to live in a specific, undesirable location. It was the worst punishment for the rich in the early imperial age, unless the crime was particularly vile, such as arson, treason, or murdering a parent or relative.

The Romans’ first prison was also its most notorious, with an ancient history stretching back to the fourth king of the city. According to UNRV, in the seventh century B.C., Ancus Marcius began the construction of a subterranean structure at the foot of the Capitoline Hill and next to the Forum Romanum. According to Atlas Obscura, the site was originally a cistern for a spring underneath the floor before it was converted into the infamous prison cell.

The small, horrifying dungeon served as either an execution chamber or a place where prisoners were confined and left to die of starvation. The sixth king, Servius Tullius, covered up the dungeon except for a tiny hole for an entrance, making the prison even more dark and terrifying. The nearly pitch-black chamber is 22-feet wide, 30-feet long, with walls only 6.5-feet high, and located more than 12-feet underground. By the third century B.C., the prison was known as the Tullianum. The Roman historian Sallust described the dungeon as “disgusting and vile by reason of the filth, the darkness and the stench.” (via UNRV).

In the late second century B.C., a far less ghastly, trapezoidal cell was added above the Tullianum to give some prisoners slightly better conditions during their confinement, including light from a small window. By the Middle Ages, the entire complex was known as the Mamertine Prison, a name most likely derived from the nearby temple of Mars Ultor.

In addition to household cells and the often-brief confinement prisoners endured before execution, there was another kind of Roman prison — those owned and operated by private creditors. Known as carcer privatus, these private prisons were used to hold citizens who failed or refused to pay their debt. In fact, imprisonment is only mentioned in the Twelve Tables when referring to laws about debt, according to Edward M. Peters.

Debtors could be imprisoned for up to 60 days if they were unable or unwilling to pay off their debt. Then, after their debt was announced publicly three market days in a row and the situation remained the same, debtors were either sold into slavery outside Rome or executed. The wealthy took advantage of these private prisons during the first century B.C., when Rome was fraught with civil war and instability. The rich targeted poverty-stricken farmers, or even innocent travelers, and forced them to labor on their massive lands and estates.

There were also prisons outside of Rome, including one at Alba Fucens in central Italy. The captured king of Macedonia, Perseus, nearly died from the terrible conditions here in the early second century B.C. According to author David J. Rothman, the historian Diodorus Siculus described the prison at Alba Fucens as an underground cell only the size of a dining room meant for nine people, but often having far more crammed in. Siculus says that the experience turned the prisoners into brutes “since their food and everything pertaining to their other needs was all so foully commingled, a stench so terrible assailed anyone who drew near it that it could scarcely be endured.”

Perseus was not set to be executed. Instead, the Roman guards provided him with a noose and a sword, hoping he would choose to commit suicide. After he refused to take his own life, the king was removed from the gruesome environment. Perseus then survived two years in a slightly better prison until his guards murdered him by depriving him of sleep. Not much else is known about prisons outside of Rome, except that Hadrian specifically prohibited provincial governors from issuing life sentences.

The demise of private prisons would not occur until the imperial age, but there were early signs that the people hated the practice. In 385 B.C., the war hero Marcus Manlius became even more popular when he tried to release a group of confined debtors. But the attempt failed, and Malius was imprisoned before being executed.

After the fall of the Republic, the emperors consolidated their power, and so private prisons were increasingly viewed as outside the law, says Invicta. In this new era, those who were caught running such prisons were imprisoned themselves in public prisons for as long as they had held others. If there had been many prisoners, the creditors had to be imprisoned for as long as they all were combined. Plus, all the debts they were owed from their captives were erased as well. But those were not the only consequences one could face — some creditors were tried and convicted of treason, which ultimately led to their execution.

As the empire got larger, the overcrowded prisons not only had to deal with more criminal cases, but also with a growing number of Rome’s enemies, says Invicta. Rebels, traitors, and Christians were not only the ones who often received the highest punishments, but they usually endured harsh confinement and brutal torture since the prisoners were so despised by the state.

Imprisonment was not usually part of the official sentence, but some Christians, including one named Ptolemaeus, endured long periods of confinement before their official punishment. However, some Christians had a slightly better experience of imprisonment because they had regular visitors. In “The Oxford History of the Prison,” author David J. Rothman explains that “among Christians, the duty of visiting prisoners was recognized as soon as the persecutions began in earnest in the second century,” and that this was a result of Jesus’ prediction that those who visited prisoners would be counted among the righteous at the Last Judgment.