Sielanka is a housing estate developed in the 1910s in the heart of downtown city Bydgoszcz, Poland. Its completion spans almost 25 years, across the political changes of the period (from the Prussian occupation to the re-creation of the Polish state). It was created in the spirit of garden city spirit originating from the beginning of the 20th century and refers to eclectic forms. In addition, there are many modernist villas, fashionable in the interwar period.