The Palace of the Inquisition sits on Plaza de Bolivar in Cartagena's old walled city. Built in the 18th century, this grand colonial building with its distinctive baroque stone entrance served as the seat of the Holy Office of the Inquisition for much of northern South America.
Inside, the museum lays out the full horror of the Inquisition's methods — racks, thumbscrews, and other instruments of torture are displayed alongside explanatory panels covering the tribunal's 200-year reign. One standout artifact is a receipt for ransom paid to Sir Francis Drake, who agreed not to burn Cartagena to the ground in exchange for a hefty sum.
The upper floors house exhibits on Cartagena's broader colonial history, and the building itself is worth admiring for its carved balconies and interior courtyard. Allow about an hour for a visit.