The Tokyo Bay Aqua-Line 「東京湾アクアライン」 is a bridge-tunnel combination which is built across Tokyo Bay in Japan. It connects the city of Kisarazu 「木更津」 in Chiba Prefecture with the city of Kawasaki 「川崎」 in Kanagawa Prefecture and provides a shorter drive between the Bōsō area in Chiba Prefecture and the Tokyo-Kawasaki-Yokohama area on the other side of the bay. With an overall length of 15.1 km, it includes a 4.4 km bridge and 9.6 km undersea tunnel which is ranked fourth-longest in the world!
At the point where both the bridge and tunnel meet, there is a man-made island called Umihotaru 「海ほたる」 (literally meaning “sea firefly”) which is a parking area with restaurants, shops and amusement facilities. It is designed in the shape of a cruise ship and has parking lots on the 1st to 3rd floors and shops, restaurants, cafes and amusement facilities on the 4th and 5th floors.
For several years I had been thinking of checking out this parking lot located in the middle of the sea, but never got around to do so until now.
At the 5th floor:
You can see part of the parking area at Umihotaru in the next two pictures…
View of the bridge in the direction towards Kisarazu in Chiba Prefecture:
There is an observation deck which commands a 360-degree panoramic view of Tokyo Bay and on a clear day you can see Mt. Fuji and the Tokyo Sky Tree.
The weather was perfect when I was there and I managed to see the outline of Mt Fuji in the distance.
After viewing Mt. Fuji, if you turn your head towards the right, you can also spot the Tokyo Sky Tree in the distance.
Various sculptures and decorations can also be found at the observation deck on the 5th floor.
Another landmark which can be seen from Umihotaru is a distinctive cylindrical-shaped man-made island, which is named Kaze no Tō 「風の塔」 (meaning “tower of wind”) and houses a ventilation station for the tunnel.
Here’s a closer look at Kaze no Tō 「風の塔」…
Standing at this spot at Umihotaru, you can try to imagine the undersea tunnel linking Umihotaru and Kaze no Tō 「風の塔」.
If you were wondering what those little white specks were at the bottom of the previous photo, here’s a closer look:
Not only is this place a parking area (rest area) for humans, it’s a rest stop for the birds too! (^o^)
On the 1st floor of Umihotaru, you can see a huge wheel-like monument – this is the cutter face of one of the shield machines used to drill the undersea tunnel. WOW!! Imagine drills being this BIG!
There is an explanation found on the sign located next to the cutter face:
(In case the words are too small for you to read in the above photo) The description being displayed on the sign is as follows:
“This is the cutter face of one of the slurry shield machines used to drill the undersea tunnel for the Tokyo-Wan Aqua-Line Highway.
The eight slurry shield machines started drilling tunnels from Ukishima, Kaze-no-To and Umi-Hotaru man-made islands, and the tunnels were joined in the respective centres under the sea to form two tubes of 9.5km length.
The 14.14-metres diameter of the shield machines is the world’s largest. The drilling operation was carried out by rotating the cutter face during 24 months between August 1994 and August 1996, when the tunnel excavation was completed.
By feeling the worn out surface of the cutter bits, you can tell the difficulties of the drilling operation.”
Here’s one last look at Umihotaru from the area on the 1st floor where the cutter face is located at:
If you are into ink stamp collecting, head to the information counter located on the 4th floor and get your free souvenir! I did this just before I boarded the bus for my next destination. ;D
Nakajimachisaki Umihotaru PA, Kisarazu City, Chiba Prefecture, 292-0071 Japan.
From Tokyo, Yokohama & Kawasaki → Kawasaki-Ukishima JCT・Ukishima IC (川崎浮島JCT・浮島IC)
From Chiba & Kisarazu → Kisarazu Kanada IC (木更津金田 IC)
From Kisarazu → Kisarazu Station East exit, Bus stop No. 8
From Kawasaki → Kawasaki Station East exit, Bus stop No. 22
Check for the departure times on the timetables found at the bus stops.
Sometimes there could be complimentary shuttle buses from Mitsui Outlet Park Kisarazu to Umihotaru (return). For year 2012, this complimentary service was available during May 2012 to Sept 2012 but only on Saturday, Sunday and holidays.