This is the monument in Podgarić, in the Bjelovarsko-bilogorska district of central Croatia.The photograph is from a book by the Dutch artist Jan Kempenaers entitled "Spomeniks, apparently the Serbian for "Monuments".
These things - and there are several more good reproductions of the Kempenaers photos here - were constructed by the Yugoslav government in the Sixties and Seventies to commemorate various events in the partisan campaigns of WW2, as well as the usual sort of "Monument to the Revolution" sort of thing. They are all very abstract, and, as you can see in the collection pictures in the blog "Crack Two" here, range from fairly well maintained to utterly destroyed.I don't think there's a deeper meaning here. I was just fascinated by the images; these vast, contextless, desolate things, a sort of abstract Ozymandias in the Balkan hills. You wonder what a passerby will think a hundred years from now, if there is anything left of them. Will they be pointed out to the tourist, their provenance described and meaning explained? Or will they be forgotten, to be chanced upon by the adventurous journeyer standing mute and incomprehensible as Linear A?