Hailar District, formerly a county-level city, is an urban district that serves as the seat of the prefecture-level city Hulunbuir in northeastern Inner Mongolia, China. Hulunbuir, due to its massive size, is a city in administrative terms only, being mainly grassland and rural. Long known as the "Pearl of the Grasslands", Hailar acts as a gateway between China and Russia. The district spans an area of 1,319.8 square kilometers, and has an estimated population of 365,000 as of 2010. The district serves as a regional center for commerce, trade, and transportation. History Hailar was founded as a Chinese fort in 1734, and during the administration of the Republic of China, it was the capital city of Xing'an Province. It was a center of agricultural production on the historical Chinese Eastern Railway. Once known as Hulun, Hailar today is a relatively small, but thriving modern industrial city of around 300,000, its population having soared from an estimated 20,000 in the mid-20th century. After the Mukden Incident in 1931, Japan invaded China's northeastern provinces and established the puppet state of Manzhouguo. Hailar Fortress, a huge underground Japanese fortress, was completed in 1937 by forced Chinese laborers. The Kwantung Army garrisoned in Manchuria built the fortress complex as one of biggest Japanese fortifications in Manchuria. Some of the fiercest fighting of the Soviet–Japanese War in August 1945 took place around Hailar. Prisoners of war and civilians were massacred by the Kwantung Army in August 1945 during the final month of World War II. The World Anti-fascist War Hailar Memorial Park, a museum and war memorial, is built on the site of the Hailar Fortress, parts of the fortress tunnels are open for public viewing. Transportation Hulunbuir Hailar Airport serves the city, with flights to Beijing and Shenyang amongst others. Hailar's railway station is the penultimate major station before Manzhouli, the port city that stands close to the Russian border. It is on the famous Western line of the Trans-Siberian express route and China National Highway 301. Trains to Harbin take about 12 hours, and 27 to Beijing. Hailar has a frequent series of buses that cover the town. Geography Hailar is located in close proximity to the Greater Xing'an Mountains, and has an elevation ranging from . Of the city's 1,319.8 square kilometers, 28 square kilometers (or 2.12%) of the district is urban. Administrative divisions Hailar is divided into 6 subdistricts and 2