1986:76 - WATERFORD: Grady's Yard, John Street, Ward of Mount Sion, Waterford

In June 1986, a second season of excavation began on the city walls at the Grady's Yard site at the southern end of the medieval city. The excavation continued for 15 weeks and was financed by the Department of the Environment under a Special Projects scheme. The work was carried out in relation to the conservation of the walls between Manor Street and John's River. It also aimed to determine the line of the defences along the river where a new motorway was to be constructed.

Work in 1986 concentrated mainly on exposing more of the large mural fort that had been discovered in the 1984/1985 season. Work to date has now revealed that this late medieval structure is oval in plan and projects from an angle in the city walls into what was once the marsh known as 'John's Pill'. Four arches, which lead into it, were defended by early gun-loops and a wall walk. The interior was filled with water.

The excavation also revealed that a channel of John's River ran through the fort, entering through the large western archway and flowing out under the eastern archway to form a moat outside the city wall. This is clearly shown in the earliest map of the fortification in this part of the city, dating to c. 1590. The purpose of the fort initially may have been to act as a haven in times of trouble for small boats navigating the river, which is a tributary of the Suir.

Excavations inside and outside the fort indicate that, after it ceased to have a military function, it was utilised for other purposes. Circa 1700 a deep layer of clay and construction material was dumped in the interior to raise the ground level for the erection of a house. This layer was rich in 17th-century finds and covered deep deposits of waterlogged organic material associated with the cattle industry.

On removing the above material it became evident that the fort had been remodelled and turned into a tannery in the 17th century. This involved the blocking of arches and the construction of large stone vats in the interior, some of which contained material associated with tanning. Documentary evidence refers to these vats as being in use in the 1660s, which is consistent with the archaeological evidence.

Below the vats, the interior of the fort had been raised by the redeposition of riverine mud. On removing this at the west, excavation to a depth of 3.5m below the modern ground level revealed the bottom of the fort. This was located on a gravel bed on either side of the channel that ran through it.

Built into the channel, a large and well-built timber structure that had collapsed under the weight of the tannery above was found. Wedge-shaped in plan, entry from the exterior was gained through the western archway of the fort. This feature may have been associated with the docking of boats in the fort. However, owing to flooding and lack of time we were unable to dismantle it, but it is hoped to return and continue work in the near future.

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