ISSYK-KUL, also called Tuz-Kul, and by the Mongols Temurtu-nor, a lake of Central Asia, lying in a deep basin (5400 ft. above sea-level), between the Kunghei Ala-tau and the Terskei Ala-tau, westward continuations of the Tian-shan mountains, and extending from 76° 10′ to 78° 20′ E. The length from W.S.W. to E.N.E. is 115 m. and the breadth 38 m., the area being estimated at 2230 sq. m. The name is Kirghiz for “warm lake,” and, like the Chinese synonym She-hai, has reference to the fact that the lake is never entirely frozen over. On the south the Terskei Ala-tau do not come down so close to the shore as the mountains on the north, but leave a strip 5 to 13 m. broad. The margins of the lake are overgrown with reeds. The water is brackish. Fish are remarkably abundant, the principal species being carp.
It was by the route beside this lake that the tribes (e.g. Yue-chi) driven from China by the Huns found their way into the Aralo-Caspian basin in the end of the 2nd century. The Ussuns or Uzuns settled on the lake and built the town of Chi-gu, which still existed in the 5th century. It is to Hsüan-tsang, the Chinese Buddhist pilgrim, that we are indebted for the first account of Issyk-kul based on personal observation. In the beginning of the 14th century Nestorian Christians reached the lake and founded a monastery on the northern shore, indicated on the Catalan map of 1374. It was not till 1856 that the Russians made acquaintance with the district.
ISTAHBANÁT, a town and district of Persia in the province of Fars. The district, which is very fertile, extends for nearly 50 m. east and west along the southern shore of the Bakhtegán lake and produces much grain, cotton, good tobacco and excellent fruit, particularly pomegranates and grapes, walnuts and figs. The town is situated in the midst of a plain 12 m. from the eastern corner of the lake and about 100 m. S.E. of Shiraz, and has a population of about 10,000. It occupies the site of the ancient city of Ij, the capital of the old province of Shabánkáreh, which was captured and partly destroyed by Mubariz ed-din, the founder of the Muzaffarid dynasty, in 1355. When rebuilt it became known by its present name. Of the old period a ruined mosque and two colleges remain; other mosques and colleges are of recent construction. At the entrance of the town stands a noble chinar (oriental plane), measuring 45 ft. in circumference at 2 ft. from the ground.
ISTHMUS (Gr. ἰσθμός, neck), a narrow neck of land connecting two larger portions of land that are otherwise separated by the sea.
ISTRIA (Ger. Istrien), a margraviate and crownland of Austria, bounded N. by the Triestine territory, Görz and Gradisca, and Carniola, E. by Croatia and S. and W. by the Adriatic; area 1908 sq. m. It comprises the peninsula of the same name (area 1545 sq. m.), which stretches into the Adriatic Sea between the Gulf of Trieste and the Gulf of Quarnero, and the islands of Veglia, Cherso, Lussino and others. The coast line of Istria extends for 267 m., including Trieste, and presents many good bays and harbours. Besides the great Gulf of Trieste, the coast is indented on the W. by the bays of Muggia, Capodistria, Pirano, Porto Quieto and Pola, and on the E. by those of Medolino, Arsa, Fianona and Volosca. A great portion of Istria belongs to the Karst region, and is occupied by the so-called Istrian plateau, flanked on the north and east by high mountains, which attain in the Monte Maggiore an altitude of 4573 ft. In the south and west the surface gradually slopes down in undulating terraces towards the Adriatic. The Quieto in the west and the Arsa in the east, neither navigable, are the principal streams. The climate of Istria, although it varies with the varieties of surface, is on the whole warm and dry. The coasts are exposed to the prevailing winds, namely the Sirocco from the south-south-east, and the Bora from the north-east. Of the total area 33.21% is occupied by forests, 32.09% by pastures, 11.2% by arable land, 9.5% by vineyards, 7.21% by meadows and 3.26% by gardens. The principal agricultural products are wheat, maize, rye, oats and fruit, namely olives, figs and melons. Viticulture is well developed, and the best sorts of wine are produced near Capodistria, Muggia, Isola, Parenzo and Dignano, while well-known red wines are made near Refosco and Terrano. The oil of Istria was already famous in Roman times. Cattle-breeding is another great source of revenue, and the exploitation of the forests gives beech and oak timber (good for shipbuilding), gall-nuts, oak-bark and cork. Fishing, the recovery of salt from the sea-water, and shipbuilding constitute the other principal occupations of the population. Istria had in 1900 a population of 344,173, equivalent to 180 inhabitants per square mile. Two-thirds of the population were Slavs and the remainder Italians, while nearly the whole of the inhabitants (99.6%) were Roman Catholics, under the ecclesiastical jurisdiction of three bishops. The local Diet, which meets at Parenzo, and of which the three bishops are members ex-officio, is composed of 33 members, and Istria sends 5 deputies to the Reichsrat at Vienna. For administrative purposes the province is divided into 6 districts and an autonomous municipality, Rovigno (pop. 10,205). Other important places are Pola (45,052), Capodistria (10,711), Pinguente (15,827), Albona (10,968), Isola (7500), Parenzo (9962), Dignano (9684), Castua (17,988), Pirano (13,339) and Mitterburg (16,056).
The modern Istria occupies the same position as the ancient Istria or Histria, known to the Romans as the abode of a fierce tribe of Illyrian pirates. It owed its name to an old belief that the Danube (Ister, in Greek) discharged some of its water by an arm entering the Adriatic in that region. The Istrians, protected by the difficult navigation of their rocky coasts, were only subdued by the Romans in 177 B.C. after two wars. Under Augustus the greater part of the peninsula was added to Italy, and, when the seat of empire was removed to Ravenna, Istria reaped many benefits from the proximity of the capital. After the fall of the Western empire it was pillaged by the Longobardi and the Goths; it was annexed to the Frankish kingdom by Pippin in 789; and about the middle of the 10th century it fell into the hands of the dukes of Carinthia. Fortune after that, however, led it successively through the hands of the dukes of Meran, the duke of Bavaria and the patriarch of Aquileia, to the republic of Venice. Under this rule it remained till the peace of Campo Formio in 1797, when Austria acquired it, and added it to the north-eastern part which had fallen to her share so early as 1374. By the peace of Pressburg, Austria was in 1805 compelled to cede Istria to France, and the department of Istria was formed; but in 1813 Austria again seized it, and has retained it ever since.
See T. G. Jackson, Dalmatia, the Quarnero and Istria (Oxford, 1887).