1999:021 - NAVAN FORT, Navan, Armagh

In 1994 a geophysical survey in the interior of Navan Fort revealed the existence of a sharply defined circular anomaly 30m in diameter to the north of the area between Sites A and B. Site A was a ring-barrow, and Site B a large mound. Both were excavated in the 1960s (Waterman 1997). The anomaly appeared to be two narrow features, perhaps circular-plan trenches or slots rather than ditches. There was no sign of an entrance or internal features. Overlay of plans suggested that the feature, now designated 'Site C', joined or was cut by a triple ring-slot feature found under Site A.

In 1999 four trenches were laid out at widely spaced points on the perimeter of Site C. These showed that it consisted of two concentric slots c. 0.5m wide and 0.6m deep, spaced about 1m apart. The strong geophysical signature was clearly given by the considerable amount of burnt soil, with scraps of ash and charcoal in the upper fill. Where excavation continued deeper there was evidence for close-set posts in the base of the outer slot. However, the burnt material in the upper fill at all the points where the slots were exposed appeared to have been packed or have subsided into the trench and was unlike the remains of burnt vertical timbers. The looser material in the upper filling contained a significant admixture of bone fragments, some burnt to the degree of cremation. The 58 fragments were identified by Eileen Murphy as pig, cattle and sheep/goat.

A fifth test-trench was laid out c. 50m to the north-west to examine a linear geophysical anomaly running roughly parallel to the inner edge of the main enclosure ditch. A deep slot, packed with charcoal-rich soil and stones, was found on the expected line but stopped abruptly in the middle of the excavation trench.

One of the excavation trenches was laid out over the area of intersection between Site C and Site A, Phase A. This showed that Site C was earlier than the bank of Site A, but rabbit burrows had disturbed the burnt ashy layers underneath and it was not possible to determine the precise relationship between Site C and Phase A of Site A. This area will be reopened in a future season to examine deposits that survive below the disturbed zone.

One of the palisade slots, Z', running east from the 'northern enclosures' of the Site B excavation, was found in a small trial-trench. Its point of intersection with Site C was excavated. This showed that Site C clearly cut through Z', providing a valuable link back into the pre-mound stratigraphy recorded in the 1960s. Site C was later than a point in time around the middle of Site B, Phase 3 (ii–iii), around 150 BC. Four 14C determinations were carried out on charcoal collected from the filling of the inner and outer slots, two from each slot in different excavation trenches. All four dates lie within the range cal. 400 BC–AD 26. Site C is therefore a part of the Iron Age sequence of structures on the Navan Hill and may well also have been used for ceremonial purposes.

A further season of investigation is planned for 2000, when the excavation of three trenches begun in 1999 will be completed. The main thrust of the work will be to study in detail the deposits in the slots, in particular the evidence for infilling with burnt soil, the existence of structural timbers and the distribution of burnt and unburnt bone fragments in the slots. Traces of what may prove to be a third slot with much cleaner fill, between the two containing burnt material, were uncovered at the end of the 1999 season. These features will be fully explored. Another, detailed geophysical survey of Site A is planned in 2000 in the hope of identifying internal features such as pits or smaller structures, potential targets for further sampling excavation.

Reference:
Waterman, D.M. 1997 Excavations at Navan Fort 1961–71. Belfast.

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