Archaeological Evaluation

Date July 2021

Event ID 1145996

Category Recording

Type Archaeological Evaluation

Permalink http://canmore.org.uk/event/1145996

NT 63871 23750 Wessex Archaeology was asked by Historic Environment Scotland (HES) to undertake a survey of the submerged remains of a medieval bridge in the River Teviot, near Ancrum. The remains of the bridge were discovered by Ancrum and District Heritage Society (ADHS) in 2018 (DES Volume 21, 111: Canmore ID: 365688). The survey took place in July 2021.

In collaboration with ADHS a photogrammetric survey, an interpretive total station survey, and close visual inspection and photography were undertaken on the bridge foundations in July 2020. Timber samples were also collected for dendrochronological analysis by Dr Coralie Mills of Dendrochronicle, and radiocarbon dating by SUERC. These added to samples previously collected by Dr Mills and ADHS in 2019.

The site consists of the remains of two foundations or pier bases of a bridge, lying submerged beneath the northern and central arches of an extant 18th-century bridge. The northern foundation is heavily eroded, with only two kerbstones and two pieces of timber visible. The southern foundation is more complete, with numerous kerbstones and timbers visible, though also vulnerable to ongoing erosion.

The location and structure of the pier bases suggest they were part of a four arched (at least partly) masonry bridge. The construction process involved the use of branders, a process not previously archaeologically witnessed in Scotland. It seems that a timber framework was constructed and pinned into the riverbed, before the stonework of the pier and cutwater was added on top.

Based on HES-funded ‘wiggle match’ radiocarbon dating at SUERC of one oak timber, and a single CARD-funded radiocarbon date of a separate timber, the southern foundation was likely built in the mid-14th century AD. Efforts continue to refine further the dating of this bridge sub-structure through dendrochronology, hampered by a current lack of reference data for this region and period.

These bridge remains represent the earliest scientifically dated in situ bridge remains in Scotland. The date of the construction of the bridge is significant as it falls within the Second Wars of Scottish Independence and around the time of the arrival of the Black Death in Scotland. For these reasons, the mid-14th century had previously not been considered particularly favourable for bridge building.

Archive: NRHE

Funders: Historic Environment Scotland; Archaeological Research Services Ltd and SUERC (for the CARD radiocarbon date)

Robert Mackintosh – Wessex Archaeology

(Source: DES Vol 22)