Hokkaido is the second largest island of Japan, separated from largest main island of Honshu with the Tsugaru Strait. The two islands are connected via undersea railway tunnel called Seikan. The largest city in Hokkaido is Sapporo.
The indigenous people of Hokkaido are called Ainu, and the history of settlements on the island goes back to 15,000 years ago. The Japanese migrated to the island starting only in the 19th century.