Hanasaki Lighthouse looks over one of Nemuro's busiest fishing ports, but the stranger sight is below it: Kurumaishi, a radial basalt formation whose Japanese name means "wheel stone." The rock spreads in a near-circular pattern, like a frozen stone flower on the shore.
It is a small stop, but a good one if you are circling the peninsula. The lighthouse, port, and black volcanic rock give a quick, physical sense of why Nemuro is a fishing town first and a sightseeing town only second.