Shanghai, one of the world's largest cities, has intense Bortle 9 light pollution across the metropolis and the densely developed Yangtze Delta around it, making genuinely dark skies a real drive away. The hills of Zhejiang to the south-west offer the nearest relief, reaching Bortle 4–5 within two to three hours. The humid, hazy subtropical climate brings frequent cloud, so clear, dry days following autumn and winter cold fronts are the best opportunities. At 31.2°N, the southern sky is well placed, with the summer Milky Way visible from a dark site.