She said: "It's the most beautiful church, a real treasure trove, but it's like a little secret, no-one seems to realise it's even here.

"There are so many nooks and crannies crammed with wonderful things, it's bursting at the seams with art and history.

"I feel so proud of it. Knowing that people have prayed here for over 900 years gives it this great feeling that surrounds you."

The church in Addington Village Road is the oldest public building in Croydon, having been open to visitors since it was founded in 1080.

The chancel of the church is its oldest part, dating from Saxon times, while the trio of windows behind the altar date from 1140. In 1180, the first tower was built.

St Mary's provided a place of worship for six archbishops until 1896 when Archbishop Edward Benson died and his successor Archbishop Frederick Temple moved to Canterbury.

Rev Males said: "The archbishops would stay in Addington Palace, where there was a chapel, but they all preferred to worship in our little church."

The church was inspected by a team of 14 volunteers, led by co-ordinator Brenda Deans, and now every detail has been captured in two volumes.

Mrs Deans said: "It was a real labour of love. It is such a gorgeous church.

"We recorded every single bit, took so many photographs – but finally we've finished.