An underground city built around a massive cylindrical well, 100 meters in diameter, with a spiral staircase running along its inner walls, granting access to various sections. The photo is taken from the 20th level below ground, looking upward. Above, a distant circle of grayish sky is visible. concrete, futuristic devices, architectural masterpiece, dark fantasy

An underground city built around a massive cylindrical well, 100 meters in diameter, with a spiral staircase running along its inner walls, granting access to various sections. The photo is taken from the 20th level below ground, looking upward. Above, a distant circle of grayish sky is visible. concrete, futuristic devices, architectural masterpiece, dark fantasy