Lost royal castle found on remote Scottish island linked to Lords of the Isles

Archaeologists have uncovered the remains of a previously unknown royal castle on Islay, a remote Scottish island that was once the power base of the Lords of the Isles. The fortress at Loch Finlaggan appears to have served as a ceremonial and administrative center for a semi-autonomous dynasty that ruled parts of western Scotland during the 13th to 15th centuries.

New archaeological evidence shows the grand fortress spanned two islands connected by a man-made causeway. On the larger island stood a substantial stone tower, roughly 60 by 60 feet, which would have housed living quarters and provided security for the king or lord. The smaller island contained a rectangular courtyard with kitchens, a chapel with burial ground, houses, workshops and a great hall where banquets were held.

During the 14th and 15th centuries the Lords of the Isles rose to power, ruling the Hebrides and parts of mainland Scotland and Ulster. They were closely associated with Scotland's MacDonald clan and were seen as a serious challenge to the Stewart dynasty. The fortress apparently had relatively modest defensive features, suggesting the MacDonalds felt secure in their heartland on Islay. The site later fell into ruin after disputes in the 15th century, and in the 1490s James IV of Scotland sent a military expedition to Finlaggan that destroyed many buildings.

Archaeological work from 1989 to 1998, including Time Team surveys in 1994, has established Finlaggan as a key center of power. A new scholarly volume by Dr David Caldwell, The Archaeology of Finlaggan, Islay, argues that the site was central to the Lords of the Isles during the 14th and 15th centuries, before fading from prominence. The work accompanies a published book by the Society of Antiquaries of Scotland that costs 40 pounds.

Dr Caldwell said the project brought together a skilled team of specialists and volunteers and that processing the data has been a central focus since the 1990s, providing a basis for further research.

Dr Caldwell's book is published by the Society of Antiquaries of Scotland, and Caldwell is set to deliver a free public lecture about Finlaggan on Saturday, November 29 in Edinburgh and online.

Separately, a separate report indicates a lost medieval castle linked to Mary Queen of Scots may have been found in South Lanarkshire. Artefacts that could confirm the existence of Eddlewood Castle have been uncovered in woodland near Hamilton. A cobbled surface, a possible drain and pottery sherds dated to the 14th and 15th century are thought to be part of the castle. Eddlewood Castle was reportedly torn down after the Battle of Langside in 1568, though the exact reasons for its destruction remain unclear.

The two discoveries—Finlaggan on Islay and Eddlewood near Hamilton—illustrate Scotland's complex medieval landscape, where dynastic power, royal contests and regional centers developed in parallel across the countryside. Historians caution that written records from the era are sparse, but archaeological work provides crucial context for understanding how these sites functioned within the broader story of medieval Scotland.