Often referred to as hillforts (a monument thesaurus non-preferred term) where they occupy elevated positions, forts are arguably the most well-known and recognisable Iron Age site type and have attracted considerable attention both in the past and over recent decades. The Atlas of Hillforts of Britain and Ireland records 76 sites within the area that fulfil their criteria. Such sites have an advantageous topographic position enhancing their visibility to and from the surrounding landscape; include substantial uni- or multivallate enclosing works; and enclose an interior area above 0.2 ha (Halliday 2019, 37–39). The majority survive as substantial upstanding remains and are assumed to date to the Iron Age. However, some have been confirmed as early medieval, while other sites show evidence of Neolithic and Bronze Age activity. Approximately 80% occur below the Highland Boundary Fault and are most numerous along the hills around the major river valleys, especially the Tay and Earn, with notable concentrations along the Ochil Hills overlooking Strathearn, around the Tay estuary and along the Sidlaw Hills. The 20% of forts that do occur in the Highland zone are predominantly found in upper Strathtay. Christison pioneered the region’s fort studies through surveys, excavation and synthesis in the 1890s and 1900s; his work remains the basis for any new field assessment. It is apt that his detailed recording of the timber-laced rampart at Castle Law, Abernethy (MPK3069; Christison and Anderson 1899), and recognition of similarities with the example which had been recently uncovered at Castle Law, Forgandenny (MPK1905; Bell 1893; Christison 1900b), has become the focus of a reassessment of this group recently. 

Castle Law hillfort excavations in 2017 ©️ Ken Ward, courtesy of Perth and Kinross Heritage Trust
Coloured landscape drawing of a circular fort, with smoke arising from a building inside its tall walls, and a large wall outside the fort, travelling down the hill.
Reconstructive drawing of Abernathey hillfort ©️ Chris Mitchell, courtesy of Perthand Kinross Heritage Trust

The key modern excavation, in 1987, at North Mains (MPK1353; Barclay and Tolan-Smith 1991), Strathallan, revealed postholes along the ditch perimeters, interpreted as fences. An internal timber roundhouse with radiocarbon dating indicating occupation between 390–110 BC, and an earlier date from an inner ditch (1740–1320 BC) suggesting Bronze Age activity on the hill was also found. 

The SERF project (2007–15) included small-scale excavation at over 10 forts along lower Strathearn and the northern slopes of the Ochil Hills. Both low and high elevation sites were targeted, from those enclosing small knolls near the strath floor (such as Hilton House, MPK3448; Law of Dumbuils, MPK3171; Jackschairs Wood, MPK1874; Green of Invermay, MPK1910; Dun Knock, MPK2004; Kay Craig, MPK1405) to prominent foothills (Castle Craig, MPK1299), and hill summits (Ben Effrey, MPK1424; Rossie Law, MPK1397; Castle Law, Forgandenny, MPK1905; Ogle Hill, MPK1419). Full publication of this extensive body of work is imminent (Poller forthcoming); however, preliminary results indicate that most were constructed between the Early and Middle Iron Ages and were often adapted or reused. Significantly, Rossie Law and Ogle Hill produced Late Bronze Age dates (Poller pers comm), with the recovery, from a secure context, of a rare, socketed Iron Age axe head of 8–4th century BC date at Rossie Law. Previously, in 1923, amidst the scree of the north slope of the Law a Bronze Age battle axe was found (Callander 1926, 257–58; Callander 1930, 146–47). Dun Knock, Dunning, produced a complete Carinated Bowl and stone axe, evidencing Neolithic activity, along with Iron Age impressed ware pottery, and a crucible and waste material from bronze casting (Poller with Campbell 2015). Re-excavation at Castle Law, Forgandenny (2013–14) revealed a complex sequence of three major constructions with an elongated, sub-rectangular fort with massive timber-laced ramparts at its centre and on the summit. The ramparts were over 5m thick, and without an entrance, and were set within two larger oval forts (Poller 2013a; Poller and MacIver 2014; Lock and Ralston 2017; Poller forthcoming). 

SERF excavations at Ben Effrey fort ©️ Perth and Kinross Heritage Trust

The Tay Landscape Partnership’s ‘Hillforts of the Tay’ project (2014–17) saw excavation at Moncreiffe fort (MPK3203) and Moredun Top (MPK5232) on Moncreiffe Hill, and Castle Law, Abernethy (MPK3069) around the confluence of the Rivers Tay and Earn (Strachan et al forthcoming). There was evidence for three phases of activity at Moncreiffe fort, one Neolithic (3365–3104 BC), and two Iron Age (around 748–403 BC and around 410–211 BC). As at Dun Knock, the nature of Neolithic activity remains unclear, and while fort construction appears to have begun in the Early Iron Age and continued into the Late Iron Age (Strachan et al forthcoming), it would seem to be part of a prolonged discontinuous activity across prehistory. Moredun Top, the larger site on Moncreiffe Hill, was found to comprise a series of three forts, an annexe and monumental roundhouse. Provisional radiocarbon dates, suggesting the forts were active between c. 534–62 BC, will be refined in due course. Notably the 5m broad ramparts of the oval summit-fort, previously mooted as the citadel of an early medieval ‘nuclear’ fort, were confirmed as Iron Age and of a rarer, more complex form of timber-framing (Ralston pers comm) than at Castle Law, Forgandenny or Castle Law, Abernethy. A small roundhouse produced evidence of a range of crafts including small-scale ironworking, decorative stone jewellery, and with a rare decorative bronze bird-headed pin interpreted as a deliberate deposition (Strachan et al 2020, 40–41; Strachan et al forthcoming). In addition to the monumental roundhouse (see PKARF section, a palisade around a large cistern was dated to the 4th–1st centuries BC, confirming a hilltop water supply for the fort’s occupation (Strachan et al 2020, 24–28; Strachan et al forthcoming). 

Excavation of Moredun hillfort in 2017 ©️ Ken Ward, courtesy of Perth and Kinross Heritage Trust
Aerial view of the excavation at Moredun, 2016 ©️ Ken Ward, courtesy of Perth and Kinross Heritage Trust
Coloured landscape drawing of a complex fort with low enclosure walls shaped like two conjoined ovals, with smoke arising from buildings inside its walls. A large circular structure can be seen inside the fort, with round building inside it, and smaller buildings surround this large building.
Reconstructive drawing of Moredun fort ©️ Chris Mitchell, courtesy of Perth and Kinross Heritage Trust

The timber-laced ramparts uncovered at the very small, oblong fort of Castle Law, Abernethy (Christison and Anderson 1899) led to the fort becoming the type-site for Childe’s Abernethy tradition, the especially northern British variant of the murus gallicus (Ralston 2006, 56). Re-excavation in 2017 aimed to assess erosion over the intervening 120-year period and was accompanied by a reassessment of the finds assemblage (Christison and Anderson 1899; Strachan et al forthcoming). The work uncovered the distinctive timber-laced ramparts, notable for their scale (about 5m wide) relative to the size of the oblong enclosed space (0.06ha). It also revealed evidence of an internal building and bronze-working, adding to the extensive assemblage of high status pre-Roman iron objects recovered by Christison and Anderson (Cook 2018; Strachan et al 2020, 46–53). While radiocarbon dating proved problematic, cattle bone recovered from a cistern by Christison and Anderson, and since stored in the National Museums Scotland, was dated to 367–197 BC. This, together with an assessment of the combined artefact assemblages, suggests that activity at the fort can be more closely dated to the middle of the Iron Age. 

The excavations of these three forts will contribute significantly to understanding of hilltop forts in the area, especially when considered alongside the work of the SERF project (Strachan et al forthcoming; Poller forthcoming). It is apt that over a century after the excavations by Bell and Christison, that this group is again the focus of study of this architectural trend for visually impressive, massive-walled enclosures on the summits of prominent, intervisible hills in this area. 

In contrast, the forts south of the Ochil Hills, such as Dumglow (MPK5647) and Dummiefarline (MPK5646) in the Cleish Hills and on Benarty Hill (MPK5637), overlooking Loch Leven, have received the least attention to date. However, these forts may be best considered in the context of the neighbouring forts on the Lomond Hills in Fife. 

There has also been little work on the forts in the uplands, such as Castle Dow  in upper Strathtay (MPK1691), An Dun in Lower Strathtummel (MPK1635) and Dun Mor on the Highland Fault Line (PK1560). Two of the three that have been excavated, Dundurn, St Fillans (MPK346; Alcock et al 1989) and King’s Seat, Dunkeld (MPK5444; Strachan and McIver forthcoming) have returned early medieval dates. While the third, Torr Hill, Aberfeldy (MPK966; Stewart 1962) failed to produce datable material. Another possible early medieval candidate is Caisteal Mac Tuathal (MPK382) on Drummond Hill, Kenmore, overlooking the confluence of the River Lyon and River Tay and Loch Tay. As a group, however, the lack of excavation leaves their date and relationship to lowland forts, as well as other settlement forms in the area, largely unknown. 

Finally, recent development-led excavation was carried out at the ploughed-out multivallate oval fort at Broxy Kennels (MPK2051; Pettitt and Hession 2019), north of Perth, as part of evaluation work ahead of the Cross Tay Link Road. While radiocarbon dating is currently lacking for the fort, a small assemblage of charred-grain and pottery was found in a souterrain in the interior which suggests that low level domestic cereal processing took place on this low knoll overlooking the River Tay between the Bronze and Iron Ages.