What is the name of the country house in 'The Mousetrap'?

The country house in Agatha Christie’s The Mousetrap is Monkswell Manor.

The play opens in the Great Hall of Monkswell Manor, a recently converted guesthouse in Berkshire. It is run by the newly married Mollie and Giles Ralston, who find themselves snowed in with a small group of suspicious guests after a murder in London is linked to the house.

The name is easy to confuse with Christie settings such as Styles Court, the country house in The Mysterious Affair at Styles, or Chimneys, the estate in The Secret of Chimneys. Monkswell Manor is specific to The Mousetrap and is central to its claustrophobic design: everyone is trapped together, and almost anyone could be hiding a connection to the crime.

Christie originally wrote the story as a radio play called Three Blind Mice, broadcast in 1947 for Queen Mary. The stage version premiered in Nottingham on 6 October 1952, before moving to London and becoming the world’s longest-running play.