Seven road bridges connect the island to the mainland of Kyushu, linking it to the cities of Sasebo and Saikai.

The heavily eroded lava plateau is mostly unsuitable for rice agriculture, with the island dominated by the Citrus unshiu orchards instead.

Up to Jōmon period the obsidian commonly found on the Hario Island was an important raw material for the stone tools.

In 1936, the Obashi bridge [ja] has connected Hario island to the Saikai city, putting the end to the ferry operations.

Currently islanders are focusing on citrus unshiu, livestock breeding and cultured pearl production, and small scale fishing too to earn a living.