The Danish physician Jens Rasmussen Hubertz (1794–1855) conducted one of the first epidemiological studies on insanity, intellectual and developmental disabilities (IDD) published in 1843 (1) and found a total number of persons with IDD of 2,000 and a prevalence of 0.9 per 1,000 population (2). After graduation, he had worked during a dysenteriae epidemic and this experience together with a trip to Germany in 1841 awakened his interest in both mental illness and IDD. His observations in Germany and also in his travels in Denmark conducting his research made him a spokesman for reform in the care and service for people with mental illness and IDD in Denmark. His research also resulted in his differentiation between mental illness and IDD and gradually he placed all his attention to the establishment of a service for people with IDD in Denmark. In 1852, he traveled to Switzerland to meet the physician Johann Guggenbuhl (1816–1863), who in 1839 had established the first known residential care facility for children with IDD in Abendberg, a mountain near Interlaken. Guggenbuhl believed in the fresh air from the mountains as part of his treatment together with good nutrition, baths, massage, exercise, and also to some extent, medication. This trip inspired Hubertz to come back and raise private funds for the establishment of the first institution in Denmark for 20 children with IDD in November 1855. With his work, he therefore became the father of the modern service for people with IDD in Denmark, but died of stroke 2 weeks after the first children moved into Gamle Bakkehuset (the Hill House). Gamle Bakkehuset has a very interesting story, which is typical for many of these institutions around the world (3). It was built back in the 1520s at the outskirts of Copenhagen, today a museum. It has served a number of functions over the years as a farmhouse, inn, private home, official home, psychiatric hospital, residential care for children with IDD, and now a museum and the first floor guest apartment for 2 h for dignitaries. It is particularly associated with the Danish Golden Age in the 1800s, when it was a popular summer social venue for the literary and intellectual establishment with, for example, the author Hans Christian Andersen (1805–1875) visiting one of the greatest Danish actresses Johanne Luise Heiberg (1812–1890) there. In 1865, the second residential care center was established (Keller) in Copenhagen and by 1940 Denmark would have all over the country 10 such centers with a total population of around 5,000 persons with IDD (4).