On April 15 2003, the Blues clinched promotion to the Premier League with a 1-0 Fratton Park win over Burnley.
Twelve days later, they defeated Rotherham, also at home, to be crowned Championship champions.
And following a final day 5-0 romp at Bradford City, Blues fans came out in their thousands on Sunday, May 11.
For that was the day an open-top bus parade was held around the city, taking the players and management from Guildhall Square to Southsea seafront.
Now you can relive those heady weeks of seemingly non-stop celebrations with this nostalgia-packed photo gallery.
33. A young fan on the pitch after Pompey had clinched the title
Picture by Matt Scott-Joynt Photo: -
34. Fans in the Milton End during the win against Rotherham
Picture by Matt Scott-Joynt Photo: -
35. Fans at the Fratton End before the game against Rotherham
Picture by Matt Scott-Joynt Photo: -
36. Paul Merson celebrates Svetoslav Todorov's second goal in the title-clinching win against Rotherham
Picture by Matt Scott-Joynt Photo: -
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