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.