DIU, an island and town of India, belonging to Portugal, and situated at the southern extremity of the peninsula of Kathiawar. The district (area 20 sq.m.), which includes the village of Goala on the mainland and the fortress of Simbor, 5 m. W., is subject to the governor-general of Goa. Pop. of the island (1921) The anchorage is protected from the sea, but the depth of water is only about 2 fathoms. The channel between island and main land is navigable only by small craft. The town is surrounded by a wall with towers at regular intervals. Its trade is decayed. There are remains of several fine ancient buildings. The cathedral of Se Matriz, dating from i6oi, was formerly a Jesuit college. The Portuguese under treaty with Bahadur Shah of Gujarat, built a fort here in 1535, but were besieged in 1538 and 1545. The second siege is one of the most famous in Indo-Portuguese history.