It was once said to have a church for every week of the year, not to mention a pub for every day.
It has two cathedrals and is said to have more standing medieval churches - 32 - than any city north of the Alps.
But the 2011 Census has revealed Norwich had the highest proportion of respondents in England and Wales reporting "no religion".
The city's figure was 42.5% compared with a figure of 25.1% for England and Wales as a whole.
The question was the only voluntary one in the census and 7.2% of people chose not to answer it.
The census found the Christian population of England and Wales had fallen by four million to 33.2 million in the past decade.
In Norwich 56,268 people reported having no religion, but the census revealed a wide range of groupings within that category.
There were 169 Spiritualists, 131 atheists and 783 said they were Jedi Knights, a reference to the Star Wars films.
Sixty-five people gave their affiliation as Heavy Metal.
The Bishop of Norwich, the Right Reverend Graham James, was sceptical about the census' findings.
"Norwich is a city of churches. They are around every corner," he said.
"It's also a centre of vibrant Christianity today.
"The cathedral is seeing hundreds of worshippers every day during December and will welcome thousands on Christmas Eve and Christmas Day."
He said there were many other large and growing churches in Norwich of all denominations.
"So it seems doubtful that Norwich is a less religious place than anywhere else in the country," he said.
"It would not have above-average churchgoing rates if that was the case.
"But it may be a place where the vibrant presence of the churches means that people have to make up their minds about faith more definitely, and that's no bad thing."
Masoud Gadir, chairman of Norfolk and Norwich Muslim Association, said there were an estimated 5,000 Muslims in Norwich.
He said he was surprised and disappointed by the findings of the census.
"I think we have lost some moral leadership," he said.
"I sometimes see people at night who are drunk and wearing hardly any clothes. There are a lot of drugs.
"If people had just a little bit of thought they might not do those things."
He said during his 25 years in Norwich he had found ordinary people very welcoming and supportive of religious and ethnic minorities.
"Each religion can offer something positive," he said.
"The whole world can be a better place if we can break this cycle of fear and violence."
'Does things differently'
Michael Loveday, chief executive of Norwich Heritage Economic and Regeneration Trust (Heart) and author of The Norwich Knowledge, said the city was one of the most religious in Europe during the Middle Ages.
As well as dozens of churches, it had six monasteries and a large number of religious hermits, including Julian of Norwich, believed to be the first woman to write a book in English.
"The city also has a massive reputation for religious radicalism," said Mr Loveday.
Norwich Quakers, including prison reformer Elizabeth Fry and anti-slavery campaigner Thomas Fowell Buxton, also made a great impact he said.
On the census findings, he said: "Norwich always does things in a different way and I'm not surprised it's stuck out of the pack again.
"I don't know what it means, really. It could be that there are still an enormous amount of caring people but they are doing it in a less formal way."
When Chloe Smith, Conservative MP for Norwich North, took her seat in Parliament in 2009, she opted to affirm rather than swear a religious oath of allegiance to the Queen.
"I count myself an atheist and I thought it was far better to be honest about that," she said afterwards.
Of the census, Miss Smith said: "Norwich has always been a non-conformist, independent city so I'm sure people will find this latest statistic very interesting.
"I believe Norwich's churches and our other religious groups are also in good health and contribute a huge amount to the life of the city and the country."
Cookery writer and broadcaster Delia Smith, joint majority shareholder of Norwich City FC, has been a devout Catholic since the age of 22.
She lives in Suffolk but on match days often worships at Norwich's Roman Catholic Cathedral of St John the Baptist.