Coordinates: 35°37′48″N 139°46′30″E / 35.63°N 139.775°E / 35.63; 139.775

Odaiba (お台場^?) is a large artificial island in Tokyo Bay, Japan, across the Rainbow Bridge from central Tokyo. It was initially built for defensive purposes in the 1850s, dramatically expanded during the late 20th century as a seaport district, and has developed since the 1990s as a major commercial, residential and leisure area. Odaiba, along with Minato Mirai 21 in Yokohama, are two of the only places in the Greater Tokyo Metropolitan area where the seashore is accessible, and not blocked by industry and harbor areas.^{[citation needed]}

Daiba (台場^?) formally refers to one district of the island development in Minato Ward. The Odaiba name is commonly used to refer to the entire Tokyo Waterfront Secondary City Center (東京臨海副都心, Tōkyō Rinkai Fukutoshin^?) which includes the Ariake and Aomi districts of Kōtō Ward and the Higashi-Yashio district of Shinagawa Ward.

The name Odaiba comes from a series of six island fortresses constructed in 1853 by Egawa Hidetatsu for 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.

Tokyo Monorail (東京モノレール, Tōkyō Monorēru^?), officially the Tokyo Monorail Haneda Airport Line (東京モノレール羽田空港線, Tōkyō Monorēru Haneda Kūkō sen^?), is a monorail system connecting Haneda Airport in Ōta, Tokyo, Japan, to Hamamatsuchō Station in Minato, Tokyo. The trains operate along an elevated line that follows the coast of Tokyo Bay. The trip from the airport to Hamamatsuchō costs ¥470 each way.

The line opened in 1964 to coincide with the 1964 Summer Olympics. Built by Hitachi Monorail, the first cars were made in Japan from the German ALWEG design (also used in the Seattle Center Monorail and the original Disneyland Monorail), and were replaced by newer models in 1969, 1977, 1982, and 1989.

Originally, the monorail only served Hamamatsuchō and the airport. The first station added in between was the Ōi Race Track in 1965, followed by Seibijō in 1967.

When the monorail began operation, the passenger terminal at Haneda Airport was located on the west side of the airfield, south of Seibijō, and this was the southern terminus of the monorail. Upon the opening of the new passenger terminal (now Terminal 1) in 1993, the monorail was extended to a new platform, and the former passenger terminal was razed to make room for an extension of Runway B. The now-unused monorail tunnel leading to the old station was leased from the Transport Ministry and therefore had to be restored to its original state prior to its handover. Although the rails were removed from the tunnel and its entrance walled off, the tunnel remains otherwise intact today below the extension of Runway B.