Daniel Radcliffe who plays Harry Potter on screen

London, Feb. 3: As a single mother struggling to make ends meet, J.K. Rowling began her writing career in a small café.

Around 325 million book sales later, she has underlined her extraordinary success by finishing the Harry Potter series in rather more upmarket surroundings.

She finished the seventh book while staying at the five-star Balmoral Hotel in Edinburgh.

Before checking out, she marked the occasion with a tantalising inscription scribbled on the back of a Roman-style bust.

It looks as if it was written hastily in marker pen, and it says: “J.K. Rowling finished writing Harry Potter and the Deathly Hallows in this room (652) on 11th Jan 2007.”

Cleaning staff are said to have found the inscription in the £300-a-night bedroom at the hotel.

She may simply have wanted to mark the end of a remarkable journey. But her fans are likely to treat the note as another fiendish clue.

According to one report, the bust depicts Hadrian, the Roman emperor who built the eponymous wall to divide Roman Britain from the “barbarians” in the north.

The hotel says the identity of the bust is incorrect, but Potter geeks are already putting two and two together to point out that Emperor Septimius Severus restored the wall, which passes close to a village in Yorkshire called Snape.

Could the message mean that Prof Severus Snape is one of the two key characters to be killed off in the final book?

The world will have to wait until July 21 to find out, when Harry Potter and the Deathly Hallows is published.