Flagstaff, Arizona, was the first city to have outdoor lighting rules, adding them in 1958. In 2001, Flagstaff became the first recognized Dark Sky City. Their rules regulate how much light can be used, what type, and where it can shine. https://www.theguardian.com/environment/2026/sep/29/night-sky-darkness-city-regulation?CMP=Share_iOSApp_Other