Sunken courtyards are a design feature in gardens where the courtyard is lower in elevation than the surrounding areas. These courtyards are often used in traditional Chinese gardens, Japanese gardens, and some European gardens. They provide a serene and intimate space for relaxation and contemplation. Pictures of sunken courtyards typically show beautifully landscaped areas with stepped terraces, pools, and decorative elements. They are known for their tranquil atmosphere and harmonious integration with nature.