Le Lignon is a pioneering housing scheme with one of the world's longest residential blocks. The complex consist of of two identical towers and more than 1 km long housing block which contains 2,780 units. With an area of 70 acres (28 ha) the population density rivals that of the island of Manhattan. Architects created a zigzag line of 84 narrow concrete and prefab sections, which allows all the apartments to be double-oriented. The 1960s utopia contains a programe of own schools, shops, medical centre, cultural and sports facilities (including a rooftop pool).