The extensive evidence for ecclesiastical sites (monasteries, hermitages, chapels and sculptured stones) has been summarised by Fisher (1998) and need not be reiterated here. More recent research includes Rachel Butter's PhD on Argyll saints (http://www.saintsplaces.gla.ac.uk/) (Butter 2007 and new work on Iona (see Iona: Case Study). However, little of the excavation at these sites has been carried out to modern standards, and Iona has been particularly badly treated given its European significance (O'Sullivan 1998). Recent geophysical work by the Orkney College Geophysics Unit for the National Trust of Scotland has demonstrated that the vallum enclosures at Iona are complex and multi-phase. Apart from Iona, the monastic sites of Inchmarnock (CANMORE ID 40268) (Lowe 2008), St Blane's (CANMORE ID 40292) (Anderson 1900; Laing et al. 1998; Duffy 2012; Geddes and Hale 2010) and Crarae (CANMORE ID 281472) (Kirby and Alexander 2009) have been excavated, while Ardnadam (CANMORE ID 40746) (Rennie 1984) and Baliscate (CANMORE ID 294740), Mull (Wessex Archaeology 2010) are the only excavated examples of medieval chapel sites which may have an early medieval phase. It has been assumed that church buildings were in wood, but recently ó Carragáin (2010) has suggested that St Columba's Shrine (CANMORE ID 21652) on Iona may date to the 8th century, and be the first of the stone-built shrines in the Gaelic world. Recent research by Waters (2011) has suggested that a number of stone-built shrine chapel sites on Islay and elsewhere, which have western doorways, are similar to Irish forms which are early medieval. These would repay excavation.
Recent reassessment of the material from Charles Thomas's excavations on Iona (Campbell and Maldonado 2016; forthcoming) has shown the presence of window glass, the first from early medieval Scotland, as well as other unique items, illustrating the importance of re-evaluating old collections of material.