Slovak adults are able to read and write. Compulsory education begins at age six, when children enter primary school; primary education takes nine years to complete. After completing primary school, students may choose among three types of secondary education: vocational or technical schools, schools of general education (gymnasia), or teacher-training institutes. Slovakia has 14 institutions of higher education. Comenius University of Bratislava was founded in 1467 and is the nation’s oldest university. Technical universities are located in Bratislava, Kosice, Zilina, and Nitra.