Cape Crillon (), known as in Japan, is the southernmost point of Sakhalin. The cape was named by Frenchman Jean-François de La Pérouse, who was the first European to discover it. Cape Sà Âya, in Japan, is located to the south, across La Pérouse Strait.
A Russian weather station, a lighthouse and a military base are all situated at Cape Crillon today. Additionally, the cape is the Russian terminus of the proposed SakhalinâÂÂHokkaido Tunnel that would connect Japan and Russia by rail.
On the western coast of the cape is the rock formation formerly known in Japanese as Kinfugan (éÂÂæ·岩, literally "Anvil Rock").
In 1808, Mamiya Rinzà  was dispatched by the Tokugawa shogunate to survey Japanese territory on Sakhalin. Having arrived at the Matsumae domain outpost of Shiranushi on the southern tip of Cape Crillon, he was directed by local Ainu to a place called where the remains of rammed earth walls were found.
By the early 20th century, the ruins had come to be known as the . In 1905, there were discovered Matsumae documents suggesting the castle had been built by Imai Kanehira.
Current archaeological evidence indicates the castle was a colonial product of the Yuan dynasty. According to the Yuanshi, the general Yangwuludai (æ¥Âå Âé¯帶) crossed the sea and built the castle of Guohuo (æÂÂ夥åÂÂ) on Sakhalin.