The river is the third-longest river in Istria, after the Raša and Mirna rivers. It is the largest river of the Slovenian coast that flows into the Adriatic Sea.[6] It is also the only Slovenian river that does not flow through settlements and that flows in its entirety over the flysch terrain.[6]
The Dragonja originates from several sources in the Šavrin Hills and flows west to the Gulf of Piran, part of the northern Adriatic Sea.[3] It is joined by two larger tributaries from the right side (Rokava and the Drnica Creeks) and one larger tributary from the left side (Poganja Creek).[3]
The Dragonja River was first attested in written sources as Argao (ablativeArgaone),[7] and in later sources as Argaone (in 670), per Argaonem (in 1035), Dragugne (in 1100), and super flumine Dragone (in 1389). The modern Slovene and Italian names (with initial D-) are derived from Slavic *Dorgon’a, from Romance d- (< ad 'at') + Argaon- (with metathesis). Ultimately, the name is of pre-Romance origin, presumably based on the Proto-Indo-European root *h2arg’- 'shining'.[8][9]
Non-linguistic accounts explain the name as based on the meandering course of the river, resembling a dragon (Italian: drago).[3]
In the lower reaches of the Dragonja, there is a territorial dispute between Slovenia and Croatia: while Croatian authorities claim that the Dragonja is a border river, Slovenia claims a strip of territory south to the river as well.[10] As of 2012[update], the last 7 kilometres (4.3 miles) of Dragonja's course is de facto border of Croatia and Slovenia.[citation needed] The disputed territory contains four hamlets and Croatia's Plovanija border crossing.[11] The Dragonja River became a district border river after World War II, when the Yugoslav-administered Zone B of the Free Territory of Trieste (FTT) was split into the Koper and Buje districts. After dissolution of the FTT in 1954 and transfer of its former Zone B to Yugoslavia, the Koper district became a part of Slovenia while the Buje district was attached to Croatia.[12]
^ abcdeTrobec, Tanja. "Dragonja" [The Dragonja]. In Šmid Hribar, Mateja; Golež, Gregor; Podjed, Dan; Kladnik, Drago; Erhartič, Bojan; Pavlin, Primož; Ines, Jerele (eds.). Enciklopedija naravne in kulturne dediščine na Slovenskem – DEDI [Encyclopedia of Natural and Cultural Heritage in Slovenia] (in Slovenian). Archived from the original on 26 April 2012. Retrieved 23 May 2012.
Blažević, Marija (1986). "Istarske rijeke" [Istrian Rivers]. Priroda: popularni časopis hrvatskog prirodoslovnog društva. Vol. 72, no. 8. pp. 228–231. ISSN0351-0662.