Plan of a narrow, sunken courtyard

Quick answer：

A narrow, sunken courtyard is a landscape design feature that incorporates a courtyard set below ground level, creating a sense of depth and privacy. The plan would typically include details such as the dimensions of the courtyard, the layout of the surrounding garden or building, and any structural elements like steps or walls. This type of design is often seen in traditional Chinese gardens and can also be found in other architectural styles.