Off the western point of the Isle of Mull sits the 3x1 mile island of Iona. The small island is the place where St Columba came from Ireland in the 6th century, bringing christianity to the picts and celts of what is now Scotland.
The current cathedral was built in the 12th century on the site of St Columba'a origina monestary - he never built a cathedral there. The cathedral is undergoing renovation, hence the green tarps and scafolding.
Columba was also the beginning of the legend of Loch Ness. See that folder for more.