Closed sunken courtyard plan

Quick answer：

A closed sunken courtyard plan is a type of garden design where a courtyard is located below the level of the surrounding ground. This design often features walls or other structures that enclose the space, creating a sense of privacy and a sheltered environment. The layout includes elements such as paths, planting areas, and structures like gazebos or pergolas. This style of courtyard is commonly found in traditional Asian architecture, particularly in Japan and China.