Japanese sunken garden rendering

Quick answer：

A sunken garden, also known as a Japanese garden, is a traditional landscape design feature in which a garden is lower than the surrounding ground level. It typically includes elements such as a pond, stepping stones, and a variety of plants. Renderings of such gardens are visual representations used to convey the appearance of the garden before it is constructed. These renderings often show the garden's layout, the placement of various features, and the overall aesthetic of the space.