This striking photograph features two of China’s most populous cities–Beijing and Tianjin–both located in the northern part of the country near the Bohai Gulf. The United Nations estimated 2010 population for the Beijing metropolitan area is approximately 12 million, with the population of the Tianjin metropolitan area estimated to be over 7 million. Taken at night time by the Expedition 26 crew, the image dramatically illustrates the extent of both metropolitan areas. The smaller city of Langfang, located midway between Beijing and Tianjin, also is clearly visible, as are several other smaller developed areas to the northeast. The dark regions surrounding the well-lit urban areas are mainly agricultural fields, with wheat and corn being the major crops. Beijing is one of the recognized ancient capital cities–and the current capital–of the People’s Republic of China. The regular grid pattern of the city is clearly visible at lower upper right; concentric rings of major roadways around the city center have been added as the metropolitan area has expanded. Tianjin is a major trade center with connection to seaports on the Bohai Gulf. The city was established following the integration of the Grand Canal of China, a major artificial waterway extending from Beijing southwards to Hangzhou. Image Credit: NASA