The name Odaiba means gun battery, and the islands were built to carry them. In the 1850s the Edo shogunate raised a line of artificial islands in Tokyo Bay to guard the city against attack from the sea. Daiba Park is the third of those batteries, still on its original ground — a national historic site, opened as a park in 1928, with the earthworks, the powder magazine and the cooking hearths still legible in the grass. An entertainment island with a piece of coastal defense underneath it is not a combination you find elsewhere.
The case for giving it half a day starts in the afternoon. Odaiba Seaside Park has sand and a promenade looking straight at the Rainbow Bridge, and since 2026 it also has a fountain, Tokyo Aqua Symphony — up to 150 meters high and 250 meters across, ten shows a day between 15:00 and 21:30, about ten minutes each, free and with no booking. The order arranges itself: the battery by daylight, the sunset from the sand, then the fountain and the bridge lighting up together.
A replica Statue of Liberty stands in front of the bridge, put up in 1998 as a temporary piece and kept from 2000. Getting there: three minutes on foot from Daiba Station on the Yurikamome line, about ten from Tokyo Teleport on the Rinkai line, or a water bus from Hinode Pier. The Yurikamome carries on a few stops to Toyosu, so an Odaiba evening and a Toyosu museum sit comfortably in the same day.