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.
5. A young Pompey fan after beating Burnley to win promotion
Picture by Mick Young. Photo: -
6. Sam Clarke, from Leigh Park, with daughter Mollie, 1, in Guildhall Square
Picture by Malcolm Wells Photo: -
7. Pompey's promotion celebrations pass the Wheelbarrow pub, Sunday May 11 2003
Picture by Malcolm Wells Photo: -
8. Pompey's team coach leaves Guildhall Square, Sunday May 11 2003
Picture by Malcolm Wells Photo: -
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