Sunda Strait

The Sunda Strait is a significant maritime passage located in Indonesia.

It sits between the islands of Sumatra and Java. This body of water serves as a vital link between the Java Sea and the Indian Ocean. The name of the strait is derived from the Sunda Kingdom. This kingdom governed the western portions of Java from 669 until approximately 1579. The name also honors the Sundanese people, who are native to Banten and West Java.

The geography of the strait follows a roughly southwest to northeast orientation. It possesses an essentially triangular shape. On its northern side, the strait features two large bays. The water is very broad and deep at the southwestern end. However, the strait narrows significantly toward the northeast. At its narrowest point, it lies between Cape Tua on Sumatra and Cape Pujat on Java. In these northeastern sections, the water becomes much shallower. This depth variation makes navigation notoriously difficult for many vessels.

Several physical factors create hazards for ships traveling through these waters. Strong tidal currents move through the strait constantly. Sandbanks also create obstacles beneath the surface. Navigators must also contend with man-made obstructions, such as oil platforms off the Java coast. Because of these shallow areas and the lack of accurate charting, the strait is often unsuitable for large modern ships. Consequently, most of these massive vessels prefer to use the Strait of Malacca instead. This makes the Sunda Strait a complex environment for maritime logistics.

The strait is dotted with many islands, many of which are volcanic in origin. The Krakatau Archipelago is one of the most notable groups. It includes the island of Rakata, which is the sole remaining peak of the original volcano. Other islands in this group include Lang, also known as Panjang or Rakata Kecil, and Sertung, also called Verlaten. A newer island named Anak Krakatau emerged from the remains of the original volcano in 1927. Other islands in the strait include Sangiang, Sebesi, Sebuku, and Panaitan. Some of these areas are now part of Ujung Kulon National Park.

In 1883, the eruption of Krakatau fundamentally altered the region. This volcanic event had profound short-term and long-term effects. The eruption produced pyroclastic flows, which are fast-moving clouds of steam and volcanic material. These flows floated on clouds of steam and caused massive destruction. The event also triggered devastating tsunamis. The human cost was immense, as tens of thousands of people were killed. On the nearby island of Sebesi, none of the 3,000 residents survived the disaster. The eruption deposited 18 to 21 cubic kilometers of ignimbrite over 1.1 million square kilometers.

History shows that the strait has been a site of significant conflict and commerce. For centuries, it served as a crucial shipping route. The Dutch East India Company used the strait as a gateway to the Spice Islands between 1602 and 1799. The waters also saw military action during World War II. On March 1, 1942, the Battle of Sunda Strait occurred as part of the larger Battle of the Java Sea. Allied cruisers HMAS Perth and USS Houston encountered a Japanese landing force near Bantam. The Japanese force included a light aircraft carrier and several cruisers and destroyers. The battle resulted in the sinking of the two Allied cruisers.

There have also been ambitious engineering proposals to connect the islands. In the 1960s and again in the 1990s, people suggested building a bridge across the strait. A specific plan announced in October 2007 proposed a four-part suspension bridge. This structure would use the islands of Ular, Sangiang, and Prajurit to reach above sea level. The maximum span would have been 3 kilometers. This would have been about 50% longer than the 1915 Çanakkale Bridge. An $11 billion agreement for a road and rail bridge was signed with China Railway Construction Corporation in 2012. However, the Indonesian government under President Joko Widodo shelved these plans in November 2014.

Today, the strait remains a biologically and economically important area. It is located within Indonesia’s Fisheries Management Area 572. This region is the focus of the Blue Halo S pilot project involving Konservasi Indonesia. Although the 1883 eruption changed the landscape, the population has recovered. Much of the coastline is now very densely populated. The strait continues to be a place of geological activity and maritime importance.