translated by Brett Larner
On May 28 Chiba Prefecture governor Kensaku Morita announced plans for the Aqua-Line Marathon, a new race which will join Chiba with the city of Kawasaki in Kanagawa Prefecture via the Tokyo Bay Aqua-Line bridge and tunnel system. Details are currently under discussion in conjunction with Kanagawa Prefecture governor Shigefumi Matsuzawa.
The first running of the new marathon is planned for March next year and will accept 20,000-30,000 runners. Current plans call for the race, which will include both a half marathon and full marathon, to start and finish at Chiba's Sodegaura Civic Sports Complex. Runners in the half marathon will turn around at the Aqua-Line's Umehotaru parking area, while marathoners will travel through the Aqua-Line's tunnel to Ukishima in Kawasaki before returning to Chiba. Both prefectures intend to work together to make the plan a reality.
Although many details such as the interruption of traffic flow on the Aqua-Line system have yet to be worked out, if the race is successfully launched it may surpass the Tokyo Marathon as the largest marathon in the country. Governor Matsuzawa commented, "I'd like to run it too."
Translator's note: The above video shows what will be the second half of the marathon course. According to the Wikipedia article linked above, the tunnel section of the Aqua-Line is 9.6 km long, the longest underwater automobile tunnel in the world. This means that after cresting the bridge's 30 m high span in the first 10 km, marathoners will run the next 10 km in a tunnel 60 m under the water, surface briefly in Kawasaki, turn around, run another 10 km through the tunnel, then climb the bridge again in the final 10 km before finishing back in Chiba. The above-water sections will be exposed on all sides to the winds on the bay, which can be considerable in March.