Ljubljana has a rich history of discoveries in medicine and innovations in medical technology. The majority of secondary and tertiary care in Slovenia takes place in Ljubljana. The Ljubljana University Medical Centre is the largest hospital centre in Slovenia. The Faculty of Medicine (University of Ljubljana) and the Ljubljana Institute of Oncology are other two central medical institutions in Slovenia. The Ljubljana Community Health Centre is the largest health centre in Slovenia. It has seven units at 11 locations. Since 1986, Ljubljana is part of the WHO European Healthy Cities Network.