 In the late 19th century, Austria-Hungary established a geodetic network, for which the elevation benchmark was determined by the Adriatic Sea's average level at the Sartorio pier in Trieste.This benchmark was subsequently retained by Austria, adopted by Yugoslavia, and kept by the states that emerged after its dissolution, including Croatia.The geographical extreme points of Croatia are Žabnik in Međimurje County as the northernmost point, Rađevac near Ilok in Vukovar-Syrmia County as the easternmost point, Cape Lako near Bašanija in Istria County as the westernmost point and the islet of Galijula in Palagruža archipelago in Split-Dalmatia County as the southernmost point.