A map of Middle-Earth annotated by J.R.R. Tolkien has been discovered in a copy of “The Lord of the Rings” owned by illustrator Pauline Baynes.

The document offers glimpses into many of Tolkien’s observations on the fictional world, which hosts the action in “The Lord of the Rings” and “The Hobbit” (and their subsequent film adaptations). To name a few, he notes that Hobbiton is on the same latitude as Oxford, England, and hints that the Italian city of Ravenna could be the inspiration behind the city of Minas Tirith.

The map is on display and up for sale at Blackwell’s Rare Books for £60,000. Blackwell’s says the map shows “the exact nature” of Tolkien’s vision.

“Before going on display in the shop this week, this had only ever been in private hands,” Henry Gott, modern first editions specialist at Blackwell’s, said. “One of the points of interest is how much of a hand Tolkien had in the poster map; all of his suggestions, and there are many, are reflected in Baynes’ version. The degree to which it is properly collaborative was not previously apparent, and couldn’t be without a document like this. Its importance is mostly to do with the insight it gives into that process.”

The map also shows the novelist using Belgrade, Cyprus and Jerusalem as reference points for the created world.

“The map shows how completely obsessed he was with the details. Anyone else interfered at their peril,” said Sian Wainwright at Blackwell’s. “He was tricky to work with, but very rewarding in the end.”