The main islands (that is, the "North" and "South" islands, and the thin island that connects them) are the largest coherent satellite island group of Nagasaki Prefecture and the fourth largest in Japan (excluding the main islands of Honshu, Kyushu, Shikoku and Hokkaido).
As illas principais (é dicir, as illas "Norte" e "Sur", e a delgada illa que as conecta) son o grupo de illas satélite máis grande da Prefectura de Nagasaki e o cuarto máis grande en Xapón (excluíndo as illas principais de Honshu, Kyushu, Shikoku e Hokkaido).