Coals to Newcastle

Selling, carrying, bringing, or taking coal(s) to Newcastle is an idiom of British origin describing a foolhardy or pointless action. It refers to the fact that historically, the economy of Newcastle upon Tyne in north-eastern England was heavily dependent on the distribution and sale of coal—by the time of the first known recording of the phrase in 1538, 15,000 tonnes of coal were being exported annually from the area—and therefore any attempt to sell coal to Newcastle would be doomed to failure because of the economic principle of supply and demand.