"The first bricks of Hogwarts were laid in a flat in Clapham Junction", she confirmed.
The "Harry Potter" book series has gone on to sell more than 500 million copies worldwide.
Rowling admitted is fairly correct, although - she stated that she did spend a big period of time writing in Nicholsons' Cafe (which, she stated, is now a Chinese language restaurant).
"The fan asked Rowling to explain "the truth about this Harry Potter" birthplace ".
Rowling, who is known to drop various unknown bombs and tidbits on the Twitter franchise, explained that the true birth of Harry Potter's "pen on paper" occurred in his apartment.
However, she claimed, the minute where she had the concept for the collection itself was while she was riding on a train.
"If you define Harry Potter's birthplace as a moment of early thought for me, it's the Manchester-London train", Rowling tweeted.
During an interview with CNN, she admitted that the creation of Hogwarts in particular came to her "by attractive places I saw or visited because it's so far from the truth".
For example, a fan from the bookstore Livariaria Lelo in Porto, Portugal, tweeted a picture that inspired the Hogwarts Library.
"If this excites people who are upset about the bookstore in Oporto, I sometimes write it here", she wrote. ".As ever in a crisis of this sort, the poorest and most vulnerable are hit hardest, so in honour of the Battle of Hogwarts, I'll be making a donation of £1m..."
Rowling has dismissed some other rumors surrounding her impulses for key symbols from the Harry Potter world.
"I sometimes hear Hogwarts is based on one of the schools in Edinburgh, but that is also 100% wrong", Rowling said.
"Hogwarts was created long before I applauded any of them!" The author was turned down by publishing houses left, right and centre while living a cash-strapped life as a single mother, but J.K. Rowling persisted in an idea she really believed in. "I did finish Hallows in the Balmoral, though, & I can't lie, I'd rate it a smidge higher than the Bournville", she went on to reveal.
"My favourite bit of utter nonsense about Potter landmarks is still this one. I was mostly sitting in places I could get a cheap coffee/could afford the rent & making it all up", she confirmed.
Unfortunately, when it concerns any kind of looters regarding upcoming job, Dumbledore articulated frustration finest: "Alas, earwax".