Somewhere beneath the routine activity of a Garda station in Waterford City, the bones of a late Elizabethan and Jacobean military fortification are quietly going about their business. The structure, once known as the Citadel, was built outside St Patrick's Gate, positioned to command a view across the entire city. It is, by any measure, an odd fate for a fort that was designed to project authority and control: the north wall survives, along with parts of the east and south walls, absorbed now into a working police station rather than a battlefield or a heritage site.

Construction may have begun as early as the 1590s under a Captain Edmund Yorke, though the fort was not completed until 1625, meaning it straddled the reigns of Elizabeth I and James I and arrived at its finished form during a period of intensive English colonial consolidation in Ireland. A bastioned fort, as a type, is a product of that era's military engineering thinking: rather than the tall, thin walls of a medieval castle, which crumbled easily under cannon fire, bastioned designs featured low, angled projections that allowed defenders to cover dead ground and absorb artillery bombardment more effectively. That the Citadel was considered worth mapping on at least three separate occasions in the seventeenth century speaks to its significance in the urban landscape of the time. It appears in varying forms on maps by Phillips from 1685 and by Goubet from around 1680, and on a further seventeenth-century map later published by the Reverend R. H. Ryland in his 1824 history of Waterford city and county.