15 February 1971 was Decimal Day in the United Kingdom when the old currency of pounds, shillings and pence with the pound being worth two hundred and forty pennies was replaced with a currency of pounds and pence with one hundred pennies in each pound.
The announcement of the change to decimal coinage came in 1966 and as hundreds of millions of new coins were needed and expansion at the existing Royal Mint at Tower Hill in London was not practical, it was decided to find a new location outside London. More than 20 sites were considered, however in keeping with the government's policy of transferring industry from the capital to development areas, Llantrisant was eventually chosen as the site for the new Royal Mint. It had a suitable 38 acre site with a readily available workforce and crucially had the backing James Callaghan, who as Chancellor of the Exchequer was Master of the Mint and also an MP for Cardiff.
Work on the new mint began in August 1967 with the first phase opened in December 1968 in time for decimalisation. The second phase of construction began in 1973 involving a progressive transfer from Tower Hill which was completed in 1975. The Royal Mint at Llantrisant now houses some of the most advanced coining machinery in the world and it has a larger capacity than any other mint in Western Europe.
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