sumatra | ethnicgroup | acehnese_people <sep> sumatra is one of the sunda islands of western indonesia it is the largest island that is fully within indonesian territory, as well as the sixth-largest island in the world at 475,80763 km2 (182,812 mi2), including adjacent islands such as the simeulue, nias, mentawai, enggano, riau islands, bangka belitung and krakatoa archipelago sumatra is an elongated landmass spanning a diagonal northwest–southeast axis the indian ocean borders the northwest, west, and southwest coasts of sumatra, with the island chain of simeulue, nias, mentawai, and enggano off the western coast in the northeast, the narrow strait of malacca separates the island from the malay peninsula, which is an extension of the eurasian continent 
acehnese people are an ethnic group in sumatra.no information