This pavilion was presented to the Date family by the daimyō (domain lord) Toyotomi Hideyoshi in the late 16th century. It served as a genteel venue for tea ceremonies and moon-viewing parties – the name means ‘a place to view ripples on the water’. Today it's a peaceful spot for sipping a bowl of whisked matcha (powdered green tea).
It's at the northern end of the park opposite Matsushima-kaigan Station.