Kirosan Observatory Park

Kirosan is a hill of 301 metres at the southern end of Oshima, one of the islands of the Inland Sea in Imabari. Its summit is laid out as a park, with a lookout facing the Kurushima Strait, and the hill lies within the Setonaikai National Park.

Below the hill runs the Kurushima Strait, counted one of the three fastest tidal races in Japan, where the water changes direction with the tide and the current can be seen from above.

Crossing it is the Kurushima Kaikyo Bridge, which is three suspension bridges joined end to end, the first structure of its kind built anywhere. The bridges are lit at intervals through the year. On a clear day the view reaches Ishizuchi, the highest mountain in western Japan, and after dark the lights of Imabari show on the far shore.

The lookout was designed by Kuma Kengo. Rather than standing on the summit it is set into it: the structure is sunk into the hilltop and planted over, so that the hill keeps its outline and the viewing deck is reached from within.

The view from the summit was chosen in 2017 as one of the eighty-eight landscapes of Shikoku.