Located on the Caribbean Island, Santa Prisca, the prison Peña Duro housed the country's most dangerous criminals, revolutionaries, mercenaries and other dark characters.

In the later years of Peña Duro, a scientific research team established themselves within the prison walls and took to experimenting on the inmates. These scientists were the ones to spearhead the government task "Project: Gilgamesh" that is responsible for the creation of the super-steroid "Venom" used by the only surviving test subject Bane.