Several cave sites in the region have produced evidence of occupation or use in the Iron Age. At Dunagoil (NMRS No. NS056SE 11) midden deposits within the cave below the vitrified fort were excavated in 1913, the recovered artefacts suggesting a similar date of use as the fort (Mann 1915; Marshall 1915). Evidence of Iron Age occupation was also uncovered within two rock shelters on Inchmarnock (NMRS No NS05NW 35 and NS05NW 42), the primary occupation deposits dating to the C4th BC (Lowe 2008). The discovery of decorated pottery, probably dating to the Iron Age, was reported from a small cave near Dun Hynish on Tiree with pottery also reported from caves at Ardmore (NMRS No and Allt Dubhaig (NMRS No. NM34NE 7) (Beveridge 1903; Coles 1958; Mithen, Pirie and Smith 2006). An intact early Iron Age pot from Uamh Ur (NMRS No NR39NE 9) on Colonsay is unusual and possibly significant, although the exact nature of its recovery remain unclear, although this cave system also contained what appear to be several occupation deposits (Symington Grieve 1880). Recovered artefacts from Keil Cave (NMRS No NR60NE 3), which was excavated between 1933 and 1935, suggest occupation in the C4th AD and after (Ritchie 1967). A fragment of Samian, along with artefacts from later periods, was excavated from the St Columba's cave near Ellary (NMRS No NR77NE 10) (Campbell 1959, 1962, 1973; Campbell and Young 1973). Given their ubiquity across Argyll and its islands it would be surprising if other caves and rock shelters were not used in the Iron Age period.
The remains of several inhumations were recovered from the excavation of MacArther Cave, Oban (NMRS No NM83SE 9) in the late 19th century and were subsequently dated to between the C5th - C3rd BC (Anderson 1895b; Saville and Hallen 1994), these being rare examples of Iron Age Burial in Scotland. Recently excavations at Dunstaffnage (NMRS No NM83SE 2) uncovered an infant inhumation in a cobble built cist, associated with an irregular row of fire-pits and a cobble pathway. The pits have been interpreted as funerary pyres located along the edge of wet ground and radiocarbon dates suggest use in the late Iron Age (C. Ellis pers. comm.).