Released in 2004 to commemorate the 50th anniversary of the first sub-four minute mile by Roger Bannister in 1954. 
 
Later re-released in 2019 as part of the Royal Mint's Culture Set to commemorate 50 years of the 50p coin. 
 
Obverse: Ian Rank-Broadley
Reverse: Depicting a runner and stopwatch (designed by James Butler)
 
*The 2019 Roger Bannister 50p coin has not been released into general circulation*