The correct sequence of the four Islands of Japan in North to South direction is as follows–Hokkaido–Honshu–Shikoku– Kyushu.
Honshu is the largest and most populous island of Japan. The island separates the sea of Japan from the North Pacific Ocean.
Hokkaido is second largest island of Japan. The Tsugaru Strait separates Hokkaido from Honshu. The two islands are connected by the undersea railway Seikan Tunnel.
Kyushu is the third largest island of Japan. Japan's most active volcano, Mt. Aso is on Kyushu Island.
Shikoku is the smallest and least populous of the four main islands of Japan.
Hiroshima, situated facing the Inland Sea on the southern coast of the Japanese island of Honshu, was at the time of the atomic bombing a city of approximately 350,000 inhabitants (including military personnel).
Nagasaki, located on the western side of the Japanese island of Kyushu, was at that time a city of approximately 250,000 persons.
