The 2001 blaze was extinguished thanks to the prompt actions of firefighters but nevertheless resulted in extensive smoke damage which took years of painstaking work to repair.
During the service this Sunday (November 21) extracts from the diary of Jo Cundy, widow of the late Bishop Ian Cundy, will be read, painting a vivid picture of the days immediately following the fire.
Among those at the service will be some of the fire officers who attended the incident, as well as members of the clergy who served at the Cathedral at that time, including the Most Reverend Stephen Cottrell, Archbishop of York, who was Canon Missioner at Peterborough in 2001 and will be joining the congregation.
The Lord Lieutenant of Northamptonshire, James Saunders Watson, and the Lord Lieutenant of Rutland, Sarah Furness, will also be in attendance, as will the architect who oversaw the programme of repairs, Julian Limentani.
The Very Revd Chris Dalliston, Dean of Peterborough, said: “We are enormously grateful for the prompt action, skilled response and generous-heartedness with which this shocking fire and its consequences were tackled 20 years ago.
"This great building has stood at the heart of the city for many centuries yet is clearly more vulnerable than we imagine and the fact that we can still worship here is a blessing that we must not take for granted.
"This service will enable us to come together to remember, but also to thank God and pray for those who continue to support and care for the Cathedral in the face of new challenges today.”
All are welcome to attend the service which begins at 3.30pm, and booking is not required. Anyone thinking of coming is asked to check the Cathedral’s Covid guidelines for worshippers beforehand.