Interesting history about Odaiba from
Wikipedia...
The name Odaiba comes from a series of six island fortresses constructed in 1853 by the Tokugawa shogunate in order to protect Edo from attack by sea, the primary threat being Commodore Matthew Perry's Black Ships which had arrived in the same year. Daiba in Japanese refers to the cannon batteries placed on the islands. In 1928, the Dai-San Daiba (第三台場) or "No. 3 Battery" was refurbished and opened to the public as the Metropolitan Daiba Park, which remains open to this day.