Rondo Island

Rondo Island ( or ), is the Indonesia's northernmost territory, located in Andaman Sea with 0.650 km² in area and elevation of 35 m above sea level. The island is one of outlying island of Indonesia in Aceh province of Sumatra region. It is administratively part of village in of Sabang City, which administration center is located on Weh Island south of Rondo. Rondo is 50 km offshore from Indonesia's Sumatra mainland. This otherwise uninhabited island, accessible only by boat, has an Indonesian military outpost with a heliport and blue-roofed barracks, an adjacent lighthouse complex with a red-roofed lighthouse keeper's house and a white skeletal lighthouse topped with a viewing gallery and lantern. 
India's southernmost territory (Indira Point) on Great Nicobar Island of the Nicobar Islands is approximately 84 miles or 135 km to the north from the Indonesia's northernmost territory on Rondo Island. Centered 21 km or 13 mile northwest of Rondo, between Indonesia and India, there is a submerged sandy and rocky coral shoal with a least depth of 51 m. Island is surrounded by a mile (1.7 km) wide reef which has steep marine slope on its edges. On the southern edge of island's reef there are small rocky islets, 14 in total lying at a distance between 0.9 to 1.7 km. Between these islets and Weh Island there is 16-20 km or 3-3.5 leagues wide safe navigable channel. Before the advent of modern shipping, the shipping between Rondo and Weh Islands was considered safer due to calmer seas.
Rondo island, nicknamed as "Guardian of Indonesia", bordering exclusive economic zones of India and Thailand, lies on the strategically important shipping route where commercial shipping vessels from and to Indian Ocean pass north of Rondo. India and Indonesia are upgrading the Sabang deepsea port under their strategic economic and military partnership to enhance the regional connectivity, safety, security, and to protect the Andaman Sea and Strait of Malacca channel between Great Nicobar Island and Rondo Island (c. 2019). Area around Rondo Island is known for the threat of piracy.
History.
Fei Xin (1385 - after 1436), a military personnel of the fleet of the Ming admiral Zheng He, in his book on countries visited by Chinese ships describes an Island in the middle of important shipping route where north Sumatran natives in dugout canoes trade precious stones, Spittle Perfume (ambergris), coconut, banana, fish organs, etc with sailors in exchange of gold coins. He describes the native religion of the region to be Buddhist, with the island having a Buddhist temple and a rock with a 3 ft long imprint of Buddha's foot. He describes habits of natives, their customs as liberal and simple but rich in form, both women and men shave their heads and cover their bodies with leaves instead of clothes. "Lung-Hsien-Hsu" was the Chinese name of the island, which has been identified with Rondo, Weh and Breueh Island in ocean of Lambri (an Indianised north Sumatran kingdom from Srivijaya era) and Lemuria (hypothetical lost land with an ancient Tamil civilization).
A 1698-1700 CE journal of first French embassy to China also documents Rondo island en route to China.
Danish Shipliner Maersk's largest container ship ran aground off Rondo island on January 6, 1922 was a total loss.
Ecology.
Topography of the half sphere shaped island with somewhat flattened top is wooded and steepest on its north side. Island is completely covered in wet tropical forest. Fauna includes many species of snakes. Region around the island is rich in marine habitats. 
Tourism.
The island is popular with scuba divers. Sailboats can anchor at a depth of 14 m between northwest to southwest off the island only during northeast monsoon. Strong Rip tides around the island extend up to 32 km or 20 miles west to northwest.