Millom is a town and civil parish on the north shore of the estuary of the River Duddon in southernmost Cumberland, Cumbria, England. It is s…Millom is a town and civil parish on the north shore of the estuary of the River Duddon in southernmost Cumberland, Cumbria, England. It is situated just outside the Lake District National Park, about 6 miles north of Barrow-in-Furness and 26 miles south of Whitehaven.