On the waterfront at Waterford, directly in front of the Viking-built Reginald's Tower, there once sat a low, oval artillery platform that no longer exists and that most accounts of the city quietly pass over. Built sometime after 1560, it was a stone-faced structure designed with embrasures, the angled openings cut into a fortification wall to allow cannon to fire outward while exposing as little of the structure as possible to return fire. Seventeenth-century maps record it as carrying eight guns, and for well over a century it formed part of the city's waterfront defences.

In the 1680s, a Mr Dean Stanhope described it as "the lower platform supplied with seven or eight great guns, well mounted," a phrase that suggests the installation was still considered functional and respectable at that point. The structure belonged to a broader programme of coastal fortification that shaped the estuary towns of the south-east during the sixteenth and seventeenth centuries, as English Crown authority worked to secure Ireland's ports against foreign naval threats and domestic instability. By 1710, however, the blockhouse had been dismantled entirely. Charles Smith, writing in his 1746 history of Waterford, noted its removal, and that date of 1710 appears to be the last firm record of the structure in any form. Nothing of it survives above ground today.