Montrouge () is a commune in the southern Parisian suburbs, located from the centre of Paris. It is one of the most densely populated municipalities in Europe. After a long period of decline, the population has increased again in recent years. History The name "Montrouge" means Red Mountain - from mont (mountain) and rouge (red) - because of the reddish colour of the earth in this area. The name of the community was first mentioned in monastery documents in 1194. Throughout the Middle Ages, the hamlet was home to monasteries and a number of religious orders, while in the 15th century it became the site of quarries used for the reconstruction of Paris. The late sixteenth century saw the plain of Montrouge named "reserve for royal hunts", and during the seventeenth and eighteenth centuries it was known for its windmills, which have all now disappeared. On 1 January 1860, the city of Paris was enlarged by annexing neighbouring communes. On that occasion, most of the commune of Montrouge was annexed to Paris, forming what is now called Petit-Montrouge, in the 14th arrondissement of Paris. The remainder of Montrouge was preserved as an independent town. In 1875, the town gained a few thousand square metres from the neighbouring communes of Châtillon and Bagneux (principally in the neighbourhood (le quartier) called Haut Mesnil). On 8 January 2015, Municipal Police officer Clarissa Jean-Philippe was shot and killed in the commune, purportedly by Amedy Coulibaly. Coulibaly was reported to be an accomplice of Saïd and Chérif Kouachi, the suspected perpetrators of the Charlie Hebdo shooting. The next day, he was gunned down by police during a siege that left four hostages dead and several other people injured. Population Economy Industrial development started in 1925 and soon, many printing factories were to be found in the town. Most of these have disappeared today. Since the early years of the twenty-first century, professional services and telecommunications have been the main business activities. Aeronautical and electronic engineering, Alstom, Schlumberger, Siemens AG, ST Microelectronics Banking, Credit Agricole Corporate and Investment Bank Telecommunications, Orange The Papier d'Arménie (lit. Armenian Paper) Public transport Montrouge is served by Mairie de Montrouge and Barbara stations on Paris Métro Line 4, and by Châtillon – Montrouge station on Paris Métro Line 13. The Châtillon - Montrouge station is located at the border between the commune of Montrouge and the commune of Châtillon, on