The is a peninsula in Aomori Prefecture, at the northern end of Honshu island, Japan. The peninsula projects north into the Tsugaru Strait separating Honshu from Hokkaido. The western coast is on the Sea of Japan, while on its eastern coast are Aomori Bay and Mutsu Bay. Across the Tsugaru strait to the north is Hokkaido's Matsumae Peninsula, to which it is linked by the Seikan Tunnel.