Case Study: A9 Dualling Programme
Pitlochry to Killiecrankie — Non-Invasive and Invasive Archaeological Investigations
Client
Transport Scotland
Sector
Major Roads / Transport Infrastructure
Location
Perth & Kinross, Scotland
The Challenge
The A9 Dualling Programme is one of Scotland’s most significant road infrastructure upgrades, designed to improve safety, journey time reliability and connectivity along a major strategic corridor. Within that wider programme, the Pitlochry to Killiecrankie section comprises approximately 6.4km of dual carriageway, including grade-separated junctions, major river crossings and upgrades to side roads and local accesses.
For archaeology, the challenge was to deliver a phased programme of investigation that could identify, evaluate and manage impacts on cultural heritage assets ahead of construction, while maintaining a clear route into further mitigation where required.
Our Approach
The archaeological strategy was structured as a two-phase programme, combining non-invasive and invasive techniques to establish archaeological presence, character, extent and significance before any further mitigation was defined.
Phase 1 was designed to provide targeted evaluation and evidence gathering through:
- Historic building recording of the affected section of the Dunfallandy House Hotel boundary wall.
- Magnetometry detailed gradiometer survey in the northern compensatory planting areas.
- Archaeological trial trenching to test both known and unknown archaeological potential.
- Additional desk-based assessment and walkover survey for woodland areas to be felled.
Phase 2 was established as the follow-on mitigation route where required, potentially comprising archaeological excavation and/or strip, map and sample, alongside post-excavation assessment, analysis, publication and archiving.
Some Statistics
Scope of Archaeological Delivery
The project required more than isolated fieldwork. It was structured as a full archaeological service line supporting a live infrastructure scheme, from initial investigation through to reporting, archive preparation and, if triggered, further mitigation.
Phase 1 evaluation and recording
- Enhanced historic building recording.
- Detailed magnetometry survey and interpretative reporting.
- Archaeological trial trenching across a specified sample of the corridor.
- Additional desk-based, LiDAR-informed and walkover assessment.
Reporting and mitigation pathway
- Interim summary reporting on a rolling basis.
- Post-excavation assessment and formal reporting.
- Submission to HER / NRHE and OASIS workflows.
- Defined route into Phase 2 excavation, strip-map-sample and publication where instructed.
Investigation Highlights
The Phase 1 methodology was intentionally broad enough to test multiple forms of archaeological potential across the scheme while remaining tightly structured for decision-making.
Corridor-wide evaluation
- A total of 159 archaeological trial trenches were specified across suitable areas.
- Trial trenching targeted both known assets and blank areas with potential for previously unidentified remains.
- Exclusions were clearly defined for disturbed, constrained or low potential areas.
Evidence-led mitigation planning
- Geophysics and trial trenching were designed to confirm the presence, extent and character of archaeological remains.
- Results were intended to inform any required Phase 2 mitigation.
- The scope included post-excavation assessment, analysis, publication and archive deposition as part of the overall delivery model.
The Results
- Established a clear phased archaeological framework for a major trunk road infrastructure scheme.
- Combined building recording, geophysics, trial trenching and survey to create a comprehensive Phase 1 evidence base.
- Provided a defined pathway into excavation and strip-map-sample mitigation where further archaeological works are required.
- Integrated fieldwork with reporting, archiving and dissemination requirements suitable for a major public infrastructure programme.
Why Rubicon?
Projects like A9 Pitlochry to Killiecrankie demand more than excavation capacity alone. They require disciplined planning, phased delivery, technical range and the ability to support infrastructure decision-making from first investigation through to final reporting.
Phased infrastructure delivery
Structured archaeological services that move from early evaluation into mitigation, post-excavation and archive workflows without loss of programme control.
Technical breadth
Capability across historic building recording, geophysics, trenching, desk-based assessment, walkover survey and excavation-led mitigation.
Decision-ready reporting
Outputs designed to inform next-stage mitigation, programme planning and statutory historic environment processes.
Major scheme experience
A delivery model aligned to the needs of long-duration transport infrastructure schemes with multiple workstreams and formal reporting requirements.
Outcome
The A9 Pitlochry to Killiecrankie archaeological package demonstrates a robust, phased approach to heritage mitigation for major infrastructure: establishing the evidence base early, supporting informed mitigation decisions, and carrying the project through reporting, archiving and — if required — full excavation and publication.