Long Island is a populated volcanic island in Madang Province, Papua New Guinea. It is located north of the island of New Guinea, separated from it by the Vitiaz Strait. The island's interior contains a 360m deep freshwater volcanic crater lake and within that lake exists an even smaller island known as Motmot island. During the late 17th or early 18th century virtually all of the biota on the island was destroyed and has subsequently provided scientists a unique opportunity to study recolonization efforts by plants, animals, and humans. The vast majority of the buildings on the island are constructed using vernacular architecture.

Vitiaz Strait is a strait between New Britain and the Huon Peninsula, northern New Guinea.