The tropical island of Wetar belongs to the Indonesian province of Maluku and is the largest island of the Barat Daya Islands (literally Southwest Islands). It lies east of the Lesser Sunda Islands, which include nearby Alor and Timor, but it is politically part of the Maluku Islands. To the south, across the Wetar Strait, lies the island of Timor; at its closest it is 50 km away. To the west, across the Ombai Strait, lies the island of Alor. To the southwest is the very small island of Liran and, further, the small East Timorese island of Atauro. To the north is the Banda Sea and to the east lie Romang and Damar, the other principal islands of the Barat Daya Islands.
The principal towns on Wetar are Lioppa in the northwest, Ilwaki in the south, Wasiri in the north, Masapun in the east, and Arwala in the northeast. These are connected by roads. Wetar is 130 km wide east-to-west, and 45 km north-to-south. It has an area of 3600 km². It is surrounded by coral reefs and deep seas. The highest point on the island is 1412 m.
Wetar is part of a volcanic island arc which includes the other Barat Daya Islands and the Banda Islands, created by the collision of the Indo-Australian Plate and the Eurasian Plate. It is not, however, principally of volcanic origin, being instead mainly oceanic crust that has been lifted by the plate collision. The stratovolcano Gunungapi Wetar forms an isolated island to the north of Wetar.
There are a number of Timor languages branch of Malayo-Polynesian languages which are endemic to Wetar. Wetarese, which is also spoken on the nearby islands of Liran and Atauro, is one such language. Others include Aputai, Ili’uun, Perai, Talur, and Tugun. These are all spoken by small groups of about 1,000 people each. The national language Indonesian or regional Ambonese Malay are commonly used.
The main economic activity on Wetar is subsistence agriculture, principally of sago. Tortoise shells are also gathered and exported to countries where the trade is not banned. Most of the inhabitants are of Papuan descent. Most are Muslims, but there are some Christians as well.