Brotherhood and Unity Highway

The Brotherhood and Unity Highway (Croatian: Autocesta "Bratstvo i jedinstvo"; Macedonian: Автопат „Братство и единство“; Slovene: Cesta bratstva in enotnosti or Avtocesta bratstva in enotnosti, Serbian: Autoput "Bratstvo i jedinstvo", Аутопут "Братство и јединство") was a highway that stretched over 1,182 km (734 mi) across former Yugoslavia, from the Austrian border at Rateče near Kranjska Gora in the northwest via Ljubljana, Zagreb, Belgrade and Skopje to Gevgelija on the Greek border in the southeast. It was the one and only modern highway in the country, connecting four constituent states.

Construction began on the initiative of President Josip Broz Tito, who called the project the "Road of brotherhood and unity" (Autoput bratstva i jedinstva) after the motto of the League of Communists of Yugoslavia. A first section between Zagreb and Belgrade, built with the effort of the Yugoslav People's Army and volunteer Youth Work Actions, opened in 1950. The section between Ljubljana and Zagreb was built by 54,000 volunteers in less than eight months in 1958.

Its importance caused it to be colloquially named autoput or autocesta (generic Serbo-Croatian expressions for "highway", "motorway"). This use has since largely faded out, after the successor states built further motorways.

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Wikipedia