Otterswick, Sanday
Significance: a peat deposit with willow boles formed 6500 years ago and now lying below sea level

Alistair Rennie of SNH has investigated carefully the 19th century reports of a submerged forest at Otterswick. Using a JCB on the shore during one of the lowest tides on the year, Alistair has been able to re-expose the peat from beneath around 1 m of shell sand. The peat contained lumps of wood identified as Salix, remnants of stands of willow that grew to around 3 m high. The wood has been radiocarbon dated to 6500 BP and may well predate human occupation of the area. Since the demise of the woodland, sea level has risen by around 3 m. The site emphasises the threat of future sea level rises to this low-lying island.

“It is an melancholy sight to look into the open grave of what had one time been an umbrageous forest, blooming in all the sylvan beauty of stately trunk, spreading bough, and green leaves; where beasts roamed and fair birds sang.”

Walter Traill Dennison

Historic map showing site of submarine forest at Otterswick Bay

Key Geomorphological Sites

  • Yesnaby

    Significance: a coastline noted for its Devonian geology and coastal geomorphology

  • Bay of Skaill, Sandwick

    Significance: this bay lies adjacent to Skara Brae and provides evidence of the interaction between coastal processes and human disturbance between 6600 and 4400 radiocarbon years ago. The settlement first re-emerged from the dunes after a storm in 1850.

  • Den Wick, Deerness

    Significance: this site provides evidence for changing ice-flow conditions during the last ice sheet glaciation

  • Churchill Barrier No. 4

    Significance: the construction of the Churchill Barriers started in 1940 and led to a fundamental change in the pattern of tidal flow around Scapa Flow. A range of coastal landforms have been created subsequently which illustrate the fundamental control of coastal configuration on the transport and deposition of sand.

  • Rackwick, Hoy

    Significance: Rackwick lies at the southern end of two major glacial breaches on Hoy. Its well-developed moraines indicate that at the close of the last glaciation two lobes of ice retreated northwards at a time when the Pentland Firth was probably still occupied by ice.

  • Old Man of Hoy

    Significance: The Old Man is the tallest sea stack in Britain, 137 m high

  • Enegars Corrie, Hoy

    Significance: a superb corrie formed at an unusually low elevation that was last occupied by a small glacier only 11,000 years ago

  • Ward Hill, Hoy

    Significance: Ward Hill provides examples of a range of active and fossil periglacial landforms. As the highest point on Orkney it also provides evidence of the thickness of the last ice sheet

  • Flaga, Hoy

    Significance: the site of a former small corrie glacier on Hoy

  • Dwarfie Hamars, Hoy

    Significance: the site of a small corrie glacier during the Loch Lomond Stadial

  • Muckle Head raised beach, Hoy

    Significance: a raised beach deposit at 6-12 m asl buried by till

  • Saville Boulder at Scar, Sanday

    Significance: a possible Scandinavian erratic on Orkney.

  • Otterswick, Sanday

    Significance: a peat deposit with willow boles formed 6500 years ago and now lying below sea level

  • Kilns of Brin Novan, Rousey

    Significance: the Kilns of Brin-Novan is an excellent example of an interconnected series of caves, arches and blow-holes which illustrate the sequential development of these features.

  • Mill Bay, Stronsay

    Significance: this coastal section provides perhaps the best available exposure of the shelly till which is characteristic of the eastern part of Orkney

  • The Nev, Westray

    Significance: exceptional cliff scenery and dramatic cliff-top storm deposits