Discover Scotland and Explore the Geodiversity of the Agassiz Rock in Edinburgh
- Wayne Munday
- Jun 6
- 3 min read
Sip back and discover Scotland and explore the geodiversity of the Agassiz Rock a Site of Special Scientific Interest (SSSI) in Edinburgh. Located beside the disused Blackford Hill quarry within the Hermitage of Braid and Blackford Hill Local Nature Reserve in south Edinburgh. The volcanic rock surfaces within the nature reserve feature distinctive smooth grooves called striations formed by the action of abrasion by glacial ice during the last glacial period. These striations were among the first in Scotland to be recognised as evidence of glacial activity identified by Swiss naturalist Louis Agassiz in 1840 marking a crucial moment in the development of glacial theory.
The Hermitage of Braid and Blackford Hill Local Nature Reserve is a historic nature reserve featuring Old Hermitage House and a Visitor Centre along with attractions like an Ice House, a dovecot (Doocot) and an old water pump system. It has held a Green Flag award since 2011 for its quality as a greenspace. The site dates back to the 12th century, originally owned by Henri De Brad’s family before becoming a public park in 1937.
The nature reserve supports diverse habitats including woodland, scrub, grassland, wetlands and the Braid Burn stream providing shelter for wildlife such as Green Woodpeckers, Foxes, Otters, Herons, Kingfishers and Owls. It includes ancient woodland with mature Beech, Ash, and Sycamore trees some of which are possibly the tallest in Edinburgh.
One of best ways to enjoy the scenery and visit the Agassiz Rock is to take the Blackford Hill Loop a 4.8 km circular trail a year-round route that takes about 1 hour and 15 minutes to complete and is popular with walkers, runners and hikers. Dogs are welcome as long as they are kept on a lead.
Jean Louis Rudolphe Agassiz (1807–1873) was a Swiss scientist who began his career studying fish and published significant works about fossilised species. In the mid-1840s, Agassiz shifted his focus to glaciation and ice age research. Louis Agassiz visited Scotland twice. Firstly in 1840 with Charles MacLaren a geologist and editor The Scotsman newspaper. On this visit Agassiz identified striated and grooved rocks at Blackford Quarry as signs of past glaciation and The Scotsman played its part in promoting early glacial theory. Later that year Agassiz returned with geologist William Buckland and together they discovered evidence of glaciation in the Scottish Highlands and documented several glacial features such as moraines, striated and polished rock surfaces that provided additional evidence supporting Agassiz’s glacial theory.
The smooth and grooved rock surfaces of Agassiz Rock illustrate the direction of ice movement and contributed significantly to the understanding that glaciers shaped much of Scotland’s landscape. Historically, Agassiz Rock’s glacial origin had some initial skepticism by contemporaries who favoured alternative explanations. For example during the early 1830s, Charles Lyell believed that much of Western Europe had been submerged under cold seas with icebergs depositing rocks and mud on land as boulder clay and erratics or rocks that were transported from their original location and deposited elsewhere often deposited on different bedrock types or within unsorted glacial sediment called till.
Louis Agassiz disagreed arguing that these deposits were from a great ice sheet. By 1863 Sir Archibald Geikie, a Scottish geologist who was a student of Louis Agassiz's ideas about glacial geology and specifically the idea of continental glaciation recognised that glaciers had shaped Scotland’s landscape and fed an ice sheet that left behind glacial erratics when they melted. Despite Geikie’s efforts to establish the role of land ice in shaping Scotland. Lyell resisted and maintained his views for most of his life though he is believed to have gradually accepted that glaciers had moved erratics.
Agassiz Rock was among the first geological sites in Scotland to receive protection for its scientific value. Today, a plaque commemorates Agassiz’s discovery. The Agassiz Rock holds an important place in geological history both for its role in advancing glacial theory and for early efforts in site conservation in Scotland’s Quaternary geological heritage.
