Pola, a fortified seaport of Austria, near the S. extremity of Istria, at the head of a harbor of the same name (Porto di Pola), 54 m. S. of Trieste; pop. in 1869, 10,473, and of the commune formed by it and its suburbs, 16,324. Its bay is one of the most beautiful of the smaller inlets of the Adriatic, and has great advantages as a harbor, which led to its selection in 1850 as a naval station and as the site of an arsenal, dry dock, etc. The town is built on high ground near the water, and is surrounded by a bastioned wall built by the Venetians in the 15th century. With the exception of the cathedral, dating from the 9th century, there are few noteworthy buildings; but there are many remarkably well preserved and beautiful remains of the flourishing colony established here by Augustus, under the name of Pietas Julia. The principal of these are the amphitheatre (restored by the emperor. Francis in 1816), the porta aurea, a fine triumphal arch, and temples of Augustus and Diana.