Customers exchange old coins in an Oxford Street store on'D-Day', 15 February 1971(PA Archive)

On 15 February 1971, the UK stepped into a bold new era. Switching from the old currency which contained coins such as shillings and crowns, Brits were forced to come to terms with the bewilderingly foreign 'decimal' system of pounds and pence that we know today.

It marked a momentous event, and it's difficult to appreciate now the widespread panic across the country as people worried that they would struggle to adapt to 'thinking in tens' as opposed to the old two-base system of 12 pence to a shilling and 20 shillings to the pound.

Forty years on from what has come to be known as 'D-Day', we take a wistful look back at some of those pre-decimal coins, and work out what they'd each be worth in today's money.

Read more about the history of decimalisation on Bing