With the development of the rail network, Roskilde became an important hub for traffic with Copenhagen. In the 1870s and 1880s, the harbour was extended attracting industrial firms to the area. By the end of the century, there were tobacco factories, iron foundries and machine shops. At the beginning of the 20th century, Roskilde first prospered as a satellite community for Copenhagen but then, as ships increased in size, suffered from the fact that the harbour was too small and Roskilde Fjord too shallow for navigation. Industries began to move out of the harbour area but were still the largest source of employment, thanks in part to the spirits factory ("De Danske Spritfabrikker") and the slaughterhouse ("Roskilde Andelssvineslagteri").