JK Rowling celebrated finishing the seventh Harry Potter book by scribbling a note on the back of a miniature statue, according to hotel staff.
A spokesperson for the posh Balmoral Hotel in Edinburgh told CBBC Newsround that the author wrote in black marker pen on the back of a small statue.
She wrote: 'JK Rowling finished writing Harry Potter and the Deathly Hallows in this room on 11th Jan 2007.'
But sadly it's now being kept locked away so fans can't see it yet.
The hotel says it's being kept under lock and key in a safe place.
JK announced on her website on Thursday that the book would be released on 21 July 2007. The manuscript has been delivered to the companies who publish her books in the UK and America.
And the author is "busy editing", the process where she goes through the story with someone from her publishers to see if any small alterations are needed before it's printed.
There's no information yet about how long the book will be.
Some fans think that the price of Deathly Hallows could give a clue. In the UK it's £17.99 - one pound more expensive than books five and six. And in the USA it's $34.99, five dollars more expensive than the last two books.
But publishers in the UK and USA say that the bigger price doesn't necessarily mean a much bigger book, and that the increase may well have more to do with the cost of producing being higher this year.