On Monday, a Long March 4B rocket launched from China’s Taiyuan Satellite Launch Center carrying a remote-sensing satellite. This 50-year-old spaceport is located in north-central China, about 500km to the southwest of Beijing.

As often happens with the first stages of Chinese rockets launching from the inland Taiyuan facility, the spent Long March 4B booster fell downstream of the spaceport. In this case, it landed near a school, creating a predictably large cloud of toxic gas.

Unlike most of the world’s spaceports, several of China’s launch sites are located at inland locations rather than near water to avoid such hazards. For security purposes, China built three of its major launch centers away from water during the Cold War, amid tensions with both America and the Soviet Union.