The Digul is a major river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in southern Papua

Papua (Indonesian province)

Papua comprises most of the western half of the island of New Guinea and nearby islands. Its capital is Jayapura. It's the largest and easternmost province of Indonesia. The province originally covered the entire western half of New Guinea...

 province, Indonesia

Indonesia

Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

, on the island of New Guinea

New Guinea

New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...

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The swamplands upstream were known by the name "Boven Digul" (Above the Digul, in Dutch) and hosted a penal colony at Tanahmerah

Tanahmerah

Not to be confused with Tanahmerah Bay, Tanahmerah is a town on the Digul river within the interior of Western New Guinea. The town acted as a Dutch penal colony during the period when Indonesia was a colony of Holland....

 (Red Earth) in the early 20th century, when Indonesia was a colony of Holland

Dutch East Indies

The Dutch East Indies was a Dutch colony that became modern Indonesia following World War II. It was formed from the nationalised colonies of the Dutch East India Company, which came under the administration of the Netherlands government in 1800....

. As a result of the abortive 1926 revolt by the Communist Party of Indonesia

Communist Party of Indonesia

The Communist Party of Indonesia was the largest non-ruling communist party in the world prior to being crushed in 1965 and banned the following year.-Forerunners:...

 (PKI), the Dutch exiled 823 of the most troublesome revolutionaries here.

Rising on the southern slopes of Maoke Mountains, the Digul flows first south and then west to empty into the Arafura Sea

Arafura Sea

The Arafura Sea lies west of the Pacific Ocean overlying the continental shelf between Australia and New Guinea.-Geography:The Arafura Sea is bordered by Torres Strait and through that the Coral Sea to the east, the Gulf of Carpentaria to the south, the Timor Sea to the west and the Banda and Ceram...

. For much of its length it travels across a low region of extensive swamps and creates a delta

River delta

A delta is a landform that is formed at the mouth of a river where that river flows into an ocean, sea, estuary, lake, reservoir, flat arid area, or another river. Deltas are formed from the deposition of the sediment carried by the river as the flow leaves the mouth of the river...

 near Dolak (Frederik Hendrik) Island. The river has a length of 525 kilometres (326 mi) and is navigable as far as Tanahmerah

Tanahmerah

Not to be confused with Tanahmerah Bay, Tanahmerah is a town on the Digul river within the interior of Western New Guinea. The town acted as a Dutch penal colony during the period when Indonesia was a colony of Holland....

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