Thanks to W for the link.
Welcome to Liberland, the World’s Newest Country (Maybe): Travels with Vit Jedlicka, the would-be founding father of a libertarian paradise, by Gideon Lewis-Krausaug (New York Times)
Along the western bank of the Danube, more or less halfway between Zagreb and Belgrade, there rests in historic obscurity a three-square-mile teardrop of no man’s land. It is an artifact of a border dispute of long standing, and neither Serbia nor Croatia expresses a desire to rule over this unprepossessing Gibraltar-size property. The land, marshy and prone to seasonal inundation, is choked with unregulated scrub, with here and there the lone tongue of a poplar or the gentle shag of a willow. The only road is a rutted single-lane dirt track, the only existing dwelling a flimsy hunting hovel, its provenance unknown.
The absence of governmental authority on this land is due to the manipulated course of the Danube itself. By the late 19th century, the Danube was accepted as the natural border between the regions — at that point still under Austro-Hungarian control — that would become Croatia and Serbia. There, however, the river’s path was tortuous and difficult for larger boats to navigate, so engineering work was undertaken to smooth the snaking flow. The straightened Danube was a vast improvement for international riverine transport, but in the process, four large uncontiguous bulges of Croatia became stranded alone on the Serbian side, and one small pocket of Serbia, on what was now the far bank, became attached to the Croatian mass.
This latter pocket, which local residents call Gornja Siga, is the no man’s land in question.