Berlin has a special architectural treasure: six residential estates in the Modern Style, built between 1913 and 1932, are remarkable both for their high international importance and their good state of preservation. They are Falkenberg Garden City (Treptow), Schillerpark Estate (Wedding), the Horseshoe Estate (Neukölln), Carl Legien Estate (Prenzlauer Berg), the White City (Reinickendorf) and Siemensstadt Estate (the 'Ring' Estate, Charlottenburg and Spandau). Architects from the Berlin Modern Style such as Bruno Taut and Hans Scharoun created outstanding architecture in response to the acute housing shortage, especially among the poorer sectors of the population. Their aim was to provide affordable dwellings with kitchens, bathrooms and balconies in buildings with daylight, air and sunshine instead of claustrophobic rear courtyards and side wings. The high quality architecture, forms of expression, floor plans and the generous provision of greenery in the estates became an international model for many reform projects in the 20th century. At the end of January 2006, the Federal Republic of Germany applied for these residential estates to be included in the UNESCO World Heritage List.