An ancient rubbish dump uncovered by chance has helped boost understanding of Scotland's past.

Archaeologists from the National Trust for Scotland have recorded a mass of 2000-year-old domestic refuse at the site on the island of Iona. The rubbish includes limpet and whelk shells along with bones from sheep, goats and a grey seal.

Shards of pottery thought to date from the late Bronze Age or Iron Age, plus flint and a large cobble stone tool were also found during the excavation last month.

National Trust archaeologist Derek Alexander stumbled upon the rubbish pit earlier in the summer after erosion revealed its existence.

Mr Alexander said: "Although this is only a small site, the finds are quite exciting as they suggest a settlement close by. Despite the obvious early Christian history of Iona, very little is known of its prehistoric settlement."

Iona is most famous as the island where St Columba is said to have landed in Scotland in the Dark Ages to spread Christianity.