does this place have any highlands or mountains?
Yes, Učka mountain range.
Istria
The geographical features of Istria include the Učka mountain range, 
what is european route e751 ? It isdefined by the Declaration on the Construction of Main International Traffic Arteries of 1975. where is it located? Rijeka, Croatia can you please describe the route? It consists of motorways, but considerable sections are either expressways or two-lane roads with at-grade intersections. can you name any person or organization who helped in its development? UNANSWERABLE what places does the route connect? It connects Croatian and Slovenian Adriatic coastal areas in the vicinity of the city of Rijeka, Istria and Slovenian Littoral. was the first city ever ruled by any dynasty? Kingdom of Italy did the city participate in any wars? World War II can you name a few famous people from here? UNANSWERABLE can you describe the international carnival? Established in 1982, it has become the biggest carnival in Croatia. Every year there are numerous events preceding the carnival itself. does this place have a twin town? UNANSWERABLE which empire ruled the second city in 1814? Yes, War of the Third Coalition. which ethnic groups reside here? "Italian", "Croatian" and "Slovene".
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Istria [SEP] Geography
The geographical features of Istria include the Učka mountain range, which is the highest portion of the Ćićarija mountain range; the rivers Dragonja, Mirna, Pazinčica, and Raša; and the Lim bay and valley. Istria lies in three countries: Croatia, Slovenia and Italy. By far the largest portion (89%) lies in Croatia. "Croatian Istria" is divided into two counties, the larger being Istria County in western Croatia. Important towns in Istria County include Pula/Pola, Poreč/Parenzo, Rovinj/Rovigno, Pazin/Pisino, Labin/Albona, Umag/Umago, Motovun/Montona, Buzet/Pinguente, and Buje/Buie. Smaller towns in Istria County include Višnjan, Roč, and Hum. The northwestern part of Istria lies in Slovenia: it is known as Slovenian Istria, and includes the coastal municipalities of Piran/Pirano, Izola/Isola and Koper/Capodistria, and the Karstic municipality of Hrpelje-Kozina.