Odaiba Kaihin Park

Odaiba Kaihin Park is on a reclaimed island in Tokyo Bay, connected to the city by the Rainbow Bridge and an automated transit line. The beach is around eight hundred metres of imported sand facing back across the water at the bridge and the Minato skyline.

The island's name comes from the daiba — gun batteries built in the 1850s to defend Edo against foreign warships, one of which survives as a park. The area was redeveloped from the late 1980s as a waterfront district, and the beach was created as part of it. What makes it interesting in a register of beaches is what it is not allowed to be: swimming is prohibited because the bay's water quality does not support it, so Tokyo built a beach that nobody may swim at.

The sand is pale imported quartz on a sheltered bay with essentially no wave. Paddling, windsurfing and small boats are permitted; swimming is not, and the prohibition is signed and enforced. Occasional supervised swimming events have been held to test whether the bay could support bathing, and the results have been mixed enough that the ban stands. Kasai Rinkai Park across the bay has the other constructed Tokyo beach, also closed to swimming, and between them they make the point clearly: this is a city that built a coastline for looking at rather than for entering.

Development is a full urban leisure district: shopping complexes, a science museum, a replica Statue of Liberty facing the bridge, and a promenade the length of the shore. The beach is free and open.

You cannot swim, and the reason is Tokyo Bay rather than the beach. What Odaiba is for is the view back at the city across the water, the Rainbow Bridge lit at night, and a stretch of imported sand in a place that had no shoreline of any kind fifty years ago.