What is the name of the Duke's estate in 'The Adventure of the Priory School'?

The Duke’s estate in “The Adventure of the Priory School” is Holdernesse Hall.

The Duke of Holdernesse is one of the most powerful figures in the story, and his ten-year-old son, Lord Saltire, disappears from the Priory School. Holmes and Watson travel to the north of England to investigate, eventually visiting the Duke’s nearby house, Holdernesse Hall, as they follow the trail.

The estate is important to the mystery because the case involves the Duke’s family, his estranged wife and his secretary, James Wilder. Holmes discovers that Wilder is the Duke’s illegitimate son and has arranged the kidnapping to pressure his father into changing his will. The criminal scheme is carried out with help from the innkeeper Reuben Hayes, who murders the German master Heidegger.

One of the story’s memorable clues is the trail of supposed cow hoofprints across the moor. Holmes realizes that the marks were made by horses fitted with special shoes shaped like cow hooves. The original story ends with the Duke rewarding Holmes £6,000, while Wilder is sent to Australia and Lord Saltire is brought safely home.