Description

The monument comprises the remains of a medieval castle visible as turfed-covered footings located on a prominent rocky outcrop itself modified for defensive purposes.  A mid-20th century concrete structure is located on the highest part of the site.  There are extensive views along the coast and out to sea.

The castle was built to take advantage of the terracing and natural defences of a prominent rocky hill. The highest part of the outcrop is roughly triangular in shape and measures about 62m north-south and about 38m east-west at its broadest point.  The slopes have been quarried to enhance their defensive qualities and the summit is accessed by a ramped area of ground at the northwest angle. The summit is occupied by an inner courtyard formed by a central tower with ranges of surrounding buildings arranged in a triangle to best exploit the available land. To the north and south there are further footings of structures between the courtyard buildings and the scarped edge of the outcrop.  A lower terrace to the east of the summit seems to have been an ancillary courtyard.  On the lower slopes of the hill are the footings of other buildings including a possible later longhouse which is located to the south of the castle.

The scheduled area is irregular on plan to include the remains described above and an area around them within which evidence relating to the monument's construction, use and abandonment is expected to survive, as shown in red on the accompanying map.  The scheduling specifically excludes, but extends up to, the post and wire fences to the east and west of the monument and all above ground elements of the 20th century concrete structure on the summit of the hill. 

Source: Historic Environment Scotland

Statement of Scheduling

Cultural significance

The monument's cultural significance has been assessed as follows:

Intrinsic Characteristics

The monument is the complex turf-covered remains of a medieval castle on a rocky outcrop augmented to improve the defensive nature of the site.  Although the upstanding structures are truncated, they are in a stable condition and there is high potential for the survival of buried archaeological deposits, artefacts and ecofacts within, beneath and around the upstanding structures and associated with the rock cut defences.  The remains of the castle and associated buried archaeological deposits have the potential to provide information about the date and character of the site, the form and function of the buildings and the nature of the defences, while any artefacts and ecofacts would enhance understanding of the economy, diet and social status of the occupants, as well as provide information about land use and environment.

The date of the visible remains is unknown but a tradition, which has its origins at least as early as the 17th century, states that the remains are of a castle started early in the 16th century under William, 2nd Earl of Caithness but left unfinished after his death at the battle of Flodden (1513). The castle is depicted in Robert Gordon's map of Caithness dated 1642, but the information is derived from Timothy Pont's late 16th century map which is now lost.  The castle is labelled as 'Knockinnen or Knock Grienen' and is represented as a castle located on a prominent hill, suggesting that it was complete at that time. The present turfed-covered structural remains are not diagnostic enough to date with certainty although the layout of the site is not inconsistent with an early 16th century date.  However, the easily defended location, the rock cut defences and complexity of the remains suggests that the site may have had earlier origins with an extended development sequence.

Contextual Characteristics

Masonry castles are a widespread class of monument throughout Scotland and the example at Knockinnan is of significance because of its complexity and situation on a prominent coastal hilltop with views along the coast and beyond to the sea.  The castle is located above the coastal strip which would have been the main route for communication by land. The castle was therefore well placed to control north-south communication by land or sea and it contrasts with many other Caithness castles often located on coastal promontories (such as Forse Castle, 5km to the east-northeast; scheduled monument reference SM621, Canmore ID 8640).  The position of the monument in the landscape therefore can enhance our understanding of the locational decisions made when siting castles

Associative Characteristics

Other than map evidence dating from the later 16th century, the earliest reference to the castle is from the late 17th century Icelandic historian Thormodus Torfaeus who mentions the site in connection with Earl Einar, 5th Earl of Orkney (885-910). He states that:

'We have no tradition concerning Earle Einar, but there is in the parish of Latheroo, in Caithnes, an old ruine which is still called Knock Einar (Knockinnan), where it is very probable Earle Einar resided while he was in that county. The place is on a rising ground, commanding an extensive prospect, so that he could not be surprised in it. One of the Earles of Caithnes began a very large building at Knock Einar, but that Earle being killed at the Battle of Flowden, the building was carried no farther,'

Although map evidence suggests the castle may have been complete in the late 16th century, rather than unfinished, and there is no known archaeological evidence for Norse occupation of the site, this early reference is significant as it points to the defensive qualities of the location, associates it with Norse rule in Caithness and links the visible remains to William, 2nd Earl of Caithness.

Statement of National Importance

The monument is of national importance because it has an inherent potential to make a significant contribution to our understanding of the past, in particular castles and high status medieval settlement in northern Scotland. The upstanding structures are probably associated with important buried archaeological deposits, giving the monument potential to enhance knowledge of the architecture, construction, maintenance, development and abandonment of late medieval castles.  The site is particularly complex and contains a variety of buildings probably serving different functions, including a later use of the site. The building foundations and associated archaeological evidence can significantly enhance our understanding of how the castle functioned and was organised, the daily life of the inhabitants, their society, economy, agriculture and industry, and their trading and other contacts.  The remains of the castle occupy a prominent position within the local landscape, on a hilltop overlooking the coastal strip and the sea. An early historical reference linking the site with Earl Einar, 5th Earl of Orkney and William, 2nd Earl of Caithness contributes to its importance, suggesting an extended development sequence. The loss of the monument would diminish our ability to understand the form, function and character of late medieval fortified houses and associated settlements in the north of Scotland and further afield.

Source: Historic Environment Scotland

Sources

Bibliography

Historic Environment Scotland http://www.canmore.org.uk CANMORE ID 8200 (accessed on 15/03/2016).

The Highland Council HER reference is MHG1252 for Knockinnan Castle and MHG39599 for Longhouse, Knockinnan Castle (accessed on 18/03/16).

Gordon, R 1642 Cathenesia descripta ex magna ejusdem charta quam lustravit et descripsit Timoth. Pont. / Opera R. Gordonii ... National Library of Scotland http://maps.nls.uk/detail.cfm?id=54 (accessed on 21/06/16).

Ordnance Survey 1st Edition Caithness, Sheet XXXIX (Inset XLIII) Surveyed: 1871 Published: 1877 http://maps.nls.uk/view/74426596 (accessed 21/06/16).

Ordnance Survey 2nd Edition Caithness-shire Sheet XXXIX & XLIII Surveyed: 1905 Published: 1907 http://maps.nls.uk/view/75804255 (accessed 21/06/16).

MacGibbon, D and Ross, T 1887-92 The castellated and domestic architecture of Scotland from the twelfth to the eighteenth centuries, 4, 298-299.

RCAHMS 1911 The Royal Commission on the Ancient and Historical Monuments and Constructions of Scotland. Third report and inventory of monuments and constructions in the county of Caithness. London. Page: 85, No. 307

Thormodus Torfaeus (translated by Rev Alexander Pope)1866 Ancient History of Orkney, Caithness & the North. Wick. 14.

Canmore

https://canmore.org.uk/site/8200/

HER/SMR Reference

http://her.highland.gov.uk/SingleResult.aspx?uid=MHG1252
http://her.highland.gov.uk/SingleResult.aspx?uid=MHG39599

Source: Historic Environment Scotland