The design of an underground level 1 square with outdoor access involves creating a public space that is open to the sky, typically situated below ground level. This design must consider factors such as ventilation, lighting, structural integrity, accessibility, and aesthetics. It often requires innovative engineering solutions to ensure the space is functional and safe. Key elements include the integration of natural light through skylights, the use of transparent materials, and the incorporation of green spaces or landscaping to enhance the environment.