Edinburgh Castle, Hospital Square

A watching brief was maintained by Kirkdale Archaeology on engineering test pits and boreholes excavated by Holequest Ltd. in the Museum Square of Edinburgh Castle. This was to test the suitability of the ground for constructing a covered walkway between the two museums in the square. Prior to conversion into firstly hospitals (in 1897), and then museums, these buildings had functioned as Ordnance stores. The site of the excavations had been a magazine built around 1677, and pulled down and replaced between 1748- 54. This was demolished in 1897, and is shown on the 1877 OS. map as a rectangular block, sitting against the W wall, physically separated from the Ordnance store to the N, and connected to the one to the S by a corridor. A blast wall ran around the E side.

The boreholes proved archaeologically very unsatisfying. The deposits sampled were generally too soft to provide a good sample, with the drill simply pushing them down, rather than collecting a sample. Where seen this deposit was always a light grey silt with many inclusions, identical to that seen in the test pits. Two of the five boreholes weren't bottomed while the northernmost produced stone with mortar attached, from a depth of 2.2 m, indicating something structural, while the two most southerly hit bedrock at depths of 5.1 m and 4.85 m.

A single sherd of white china (from the silt in the northern trench) was the only datable material noted. However the iron pipes date most of the sequence to the last c. 150 years. It seems possible that the rubble noted just over 2 m down in the N trench relates to the 1897 destruction of the magazine, with the great depth of silt representing levelling material over this. Service pipes may have been inserted at the same time as this, or cut down later through this deposit. The great depth of the deposits, particularly at the S end was notable.

Sponsor: Historic Scotland

G Ewart 1998

Kirkdale Archaeology

Throughout 1998, and into 1999, Kirkdale Archaeology maintained a watching brief during renovations within Edinburgh Castle's Hospital Square, in the NW of the castle. Hospital Square is formed by two rectangular ordnance stores, orientated EW, with a gap between them of some 27.5m, now cobbled over. The ordnance stores were both constructed in 1753, but in 1897 they were converted into hospitals, with the southern block retaining much of its' original character, while that to the N saw more drastic alterations, such as the addition of two towers projecting S from its' S face. Contemporary with these two structures was a powder magazine, built at the W end of the square, running N-S, between the two stores, but only physically connected to the S one. A protective blast wall ran N-S to the E of this magazine, connecting both the stores. In1897 this was demolished and levelled over to provide the present day square.

Excavations within Hospital Square have demonstrated the survival of substantial remains of the 1753 powder magazine. These would appear to be exclusively below floor foundations, and show the massive nature of the masonry required for a structure housing such dangerous materials. In no place were the bottom of these foundations revealed. While survival was generally good, many of the walls encountered had been damaged by service trenches cutting across the courtyard, although it seems likely that walls will survive elsewhere.

A remarkably homogenous soil deposit, which was also seen at the W end of the courtyard, seems likely to represent the infilling of a demolished structure to provide a level surface for the courtyard, presumably in 1897. While little was found connected with the use of the powder magazine, it was possible to confirm that the massive foundations of this structure survive substantially intact.

Sponsor : Historic Scotland

D Murray 1998

Kirkdale Archaeology

During the summer of 1998 work carried on intermittently on the excavations begun in Hospirtal Square in December 1997. This lead on to renovation of Hospital Square, beginning in December 1998.

Sponsor: HS

G Ewart

Kirkdale Archaeology