In the 19th century, Heerlen, like most of Limburg municipalities (Maastricht was an exception), did not partake in the Industrial Revolution and it remained largely agrarian until coal mining began in the late 19th/early 20th century. In March 1874, coal had been found at the Valkenburgerweg. However, setting up a mine is a risky long-term investment and only very few private enterprises took up the challenge and bought a concession. In 1896 Heerlen got its first railway connection to allow the transportation of coal from these first coal mines. Development was still rather slow: In 1812 Heerlen had a population of 3497, in 1900 this was still only 6646. In 1901, the national government stepped in and bought all remaining unsold concessions and set up the State Mines. In a short period of time several large state-operated coalmines began production. The population rose sharply from 6646 in 1900 to 12,098 in 1910 to 32,263 in 1930. During these early expansion years many old buildings in the centre of Heerlen were demolished. The coalmines remained central to the development of Heerlen into a modern city until the early 1960s, the period during which mayor Van Grunsven was mayor of Heerlen.