The education system in Switzerland is very diverse, because the constitution of Switzerland delegates the authority for the school system mainly to the cantons. The Swiss constitution sets the foundations, namely that primary school is obligatory for every child and is free in state schools and that the confederation can run or support universities. The minimum age for primary school is about six years in all cantons but Obwalden, where it is five years and three months. After primary schools, the pupils split up according to their abilities and intentions of career paths. Roughly 25% of all students attend lower and upper secondary schools leading, normally after 12 school years in total to the federal recognized matura or an academic Baccalaureate which grants access to all universities. The other students split in two or more school-types, depending on the canton, differing in the balance between theoretical and practical education. It is obligatory for all children to attend school for at least 9 years. The first university in Switzerland was founded in 1460 in Basel, with a faculty of medicine. This place has a long tradition of chemical and medical research in Switzerland. In total, there are 12 Universities in Switzerland; ten of them are managed by the cantons, while two federal institutes of technology, ETHZ in Zurich and EPFL in Lausanne, are under the authority of the State Secretariat for Education, Research and Innovation. In addition, there are seven regional associations of Universities for Applied Sciences (Fachhochschulen) which require vocational education and a special Berufsmatura, or a Fachmatura (a graduation by a Fachmittelschule) to study. Switzerland has a high rate of foreign students in tertiary education including one of the highest in the world of doctoral level students. Many Nobel prizes have been awarded to Swiss scientists. More recently Vladimir Prelog, Heinrich Rohrer, Richard Ernst, Edmond Fischer, Rolf Zinkernagel, Didier Queloz, Michel Mayor, Kurt Wüthrich, and Jacques Dubochet have received nobel prizes in the sciences. In total, 113 Nobel Prize winners stand in relation to Switzerland and the Nobel Peace Prize has been awarded nine times to organizations residing in Switzerland. Geneva hosts the world's largest particle physics laboratory, the CERN. Other important research centers are the Empa and Paul Scherrer Institute which belong to the ETH domain. Primary The obligatory school system usually includes primary education (Primarschule in German, école primaire in French, scuola primaria / elementare in Italian