Access to Odaiba can be an attraction in itself, as the views of the Rainbow Bridge and Tokyo's harbor and waterfront area from the Yurikamome elevated train and boats are quite spectacular. Furthermore, it is also possible to walk across the Rainbow Bridge.
The Yurikamome is an automated, elevated train with rubber tires, which connects Shimbashi Station on the JR Yamanote Line with all of Odaiba's attractions and Toyosu Station on the Yurakucho Subway Line. Trains depart every few minutes, and a ride between Shimbashi and Daiba Station takes 15 minutes and costs 310 yen. If you ride the Yurikamome more than twice, a one day pass for 800 yen is likely to cost less than regular fares.
The Yurikamome crosses the Rainbow Bridge to get to Odaiba and offers spectacular views of the harbor and the Tokyo waterfront. Sit or stand at the very front of the train for the most impressive views.
By Rinkai Line
The Rinkai Line connects Osaki Station on the JR Yamanote Line with Shin-Kiba Station on the JR Keiyo Line, stopping at the Tokyo Teleport and Kokusai Tenjijo underground stations on Odaiba along the way. Some trains on the JR Saikyo Line continue to run on the Rinkai Line and provide direct connections between Shinjuku, Shibuya and Odaiba.
The ride from Shinjuku to Tokyo Teleport Station on Odaiba takes 25 minutes and costs 480 yen. Note that the Japan Rail Pass, Seishun 18 Kippu and similar JR tickets are not valid on the Rinkai Line between Osaki and Shin-Kiba, even though the line is served by JR trains.
Tokyo Water Bus operates boats between Odaiba Seaside Park and Hinode Pier (20 minutes, 460 yen, 1-2 boats per hour), where there are connections to Asakusa. Direct boats connect Asakusa and Odaiba less frequently (50 minutes, 1520 yen). Furthermore, there are boats from Hinode Pier to Palette Town and Tokyo Big Sight (25-35 minutes, 400 yen, one boat per hour except Mondays and Tuesdays).
Crossing Rainbow Bridge on foot
It is possible to cross the Rainbow Bridge on foot. The walk across takes about 30-45 minutes and offers nice views of the waterfront area. The pedestrian path begins a short walk from Shibaura-futo Station along the Yurikamome on the "Tokyo side" of the bridge, while Odaiba Kaihinkoen Station is the nearest station on the "Odaiba side". Bicycles are not allowed.
Note that the pedestrian walkways gets closed during the night (21:00 to 9:00 from April to October, 18:00 to 10:00 from November to March), on the third Monday of every month, from December 29 to 31, during the Tokyo Bay Fireworks Display and during bad weather.
Orientation in Tokyo