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In the novel Sleeping Murder, Saltmarsh House is a nursing home in Norfolk where Major Halliday spent the last years of his life. It is located six miles inland from the coast and about five mists from the town of South Benham which has a good train service to London.

Gwenda and Giles Reed paid a visit to Saltmarsh House in order to seek background information about her father. They met Dr Penrose who works at the sanatorium. He briefed them on the case notes of her father (Dr Penrose was a junior at that time) and he also gave them a diary which Major Halliday had kept.