The Strait of Malacca is a narrow stretch of water, 800 kilometres long and from 65 to 250 km wide, between the Malay Peninsula to the northeast and the Indonesian island of Sumatra to the southwest, connecting the Andaman Sea and the South China Sea. As the main shipping channel between the Indian and Pacific oceans, it is one of the most importan…The Strait of Malacca is a narrow stretch of water, 800 kilometres long and from 65 to 250 km wide, between the Malay Peninsula to the northeast and the Indonesian island of Sumatra to the southwest, connecting the Andaman Sea and the South China Sea. As the main shipping channel between the Indian and Pacific oceans, it is one of the most important shipping lanes in the world.