Rebus creator Ian Rankin is among the group of puzzled people who cannot fathom the meaning of these messages.
Walkers and cyclists have been confused by the large pile of boulders on the Shore Walk between Cramond and South Queensferry, which goes through Dalmeny Estate.
Each stone has been sprayed with a number in yellow or white spray paint – with a message asking “can you solve the puzzle?”
Another boulder has the phrase: “How many rocks did you guess? 1061?”
Passers-by have been posting pictures of the strange spectacle on social media, leading to a variety of theories.
City author Rankin – whose police officer character Rebus has solved dozens of bizarre mysteries in his popular crime novel series – was among the many Twitter followers to add his voice.
He asked his friend, author and magician Richard Wiseman, if he could shed any light on it but was left none the wiser.
The comments stemmed from a picture of the stones which was tweeted by Edinburgh-based author Ken MacLeod.
Mr MacLeod, a writer in residence at Edinburgh Napier University, said: “Numbered rocks near Cramond. What’s this? Anyone?”
His picture prompted wide online speculation about what the numbers could mean.
Gareth Powell said: “World’s most fiendish jigsaw?”
While Jenny Turner asked if it was a “geocache”, referring to an activity in which participants use a Global Positioning System (GPS) receiver or mobile to hide and seek containers, called “geocaches” or “caches”. Meanwhile, Sean McPartlin tweeted: “It’s what they do when they demolish and then rebuild ancient buildings isn’t it? Roman remains?”
Kip Williams dubbed the stones “DIYhenge”. While Tris Kerslake questioned whether the collection was a “dramatic re-enactment of a terminal moraine”, a group of rocks which forms on the edge of a glacier.
Health blogger Suzy Gow had been cycling from Granton to Queensferry with her husband John on Sunday when they came across the strange sight and took photographs of it.
She said: “I don’t think we were too far from Dalmeny House. I just assumed it was whoever managed the estate that numbered the rocks.
“I thought they were part of an old building that they may need to re-assemble. I just thought the message was funny.”
She said she was intrigued to know why the rocks were all numbered and placed in such a way.
And the mystery remains unsolved, as a member of staff at Dalmeny Estate refused to comment on the bizarre messages, which are thought to have been on the popular path since the middle of last week.
One staff member would only say: “This is a private property. There is no comment to be made.” Dalmeny House is the home of the Earl and Countess of Rosebery, who own Rosebery Estates.
The mansion is open to visitors in the summer and also hosts corporate functions.
The Shore Walk from Cramond to South Queensferry, which passes through Dalmeny Estate, is now also part of the John Muir Way, which runs from Helensburgh, Argyll and Bute, to Dunbar.