
When I published my previous piece on Minato Mirai, a friend of mine accused me of selling out and going “mainstream.” This is after all a site dedicated to bringing you the top attractions off of Japan’s beaten path so Yokohama’s best known spot might not have been the best of choices. Though I do love Minato Mirai’s history and stand by my decision to include it, today we’ll be getting back to the regularly scheduled “moss and tombs and shit” (his words, not mine). This time we will be examining the ruins of Japan’s very first man-made island that date back to the early 1200s so buckle your seatbelts; this one is going to be a journey to a very obscure spot that even many locals don’t know about!
Known as Wakaejima, this relic’s name comes from an old alias for the beach off of which the island is located. Situated right on the coast in Kamakura’s Sagami Bay, the small, man-made landmass functioned as both a breakwater and a wharf for the shogunate and eventually grew into a bustling port. During the Kamakura period (1185–1333) when the area was Japan’s functional capital, the bay was busy with merchants hailing from domains as far as China’s Sung Dynasty. Given that the Kamakura valley is surrounded on the north, east and west sides by mountains, this point of entry was a vital for both commerce and supplies.

Sagami Bay is notorious for having strong winds and being dangerously shallow making accidents between ships common. Initially Kamakura leadership tried to overcome this problem with the temporary solution of barges to ferry goods ashore. Eventually a Buddhist priest came up with the idea for Wakaejima and petitioned the shogunate to finance its construction. The hub was was created to serve as a local safe haven to call port and greatly reduced the number of incidents in Sagami Bay. An artist’s rendition of the final results of this engineering marvel can be seen pictured above.
Through the piling up of rocks in the waist-deep waters of Sagami Bay, the shogunate was able to conceive a primitive, ancient harbor where trade ships could seek refuge during treacherous seas. Wakaejima was later gradually built upon and repaired until it was finally abandoned in the end of the Edo period (1603–1868). Today many of the stones have fallen beneath the sands but the contours of Wakaejima can still be see off the coast when the tide is low.
How to Get There

Wakaejima is located on the far end of the Zaimokuza beach, a name that refers to the eastern portion of the 3.2 km Yuigahama strip. Unless you’re staying in the area, the journey to Wakaejima will begin at Kamakura station. As only the JR Shonan-Shinjuku Line and JR Yokosuka Line stop at Kamakura, this means you’ll be looking at taking either one of those two lines. To find out which is faster, consult Jorudan for the train schedules when departing. Some trains go only as far as Ofuna station so mindful of this when traveling to Kamakura.
Once you’re at Kamakura station, the island can be reached in about 15 minutes on foot. Simply follow the main Wakamiya-Oji Street all the way until you reach Sagami Bay and then turn left. The remains of Wakaejima sits at the very end of Zaimokuza beach and can be identified as a 200m mound protruding from the waves. Though finding the site is pretty straight forward, just in case here’s a map to guide you should you get lost.
Wakaejima’s Ruins

Unfortunately today Wakae Island is really only reachable during extremely low tides (unless you have a boat or don’t mind getting wet that is). When the tide is in, it is almost impossible to see any of the remnants so be sure to check far in advance so you can time your trip accordingly. Luckily we live in a world where one need not be a fisherman that is hyper attuned to the seas to do this! Here’s a tidal chart for Kamakura that should be accurate enough for our purposes. Just be sure to not do what I did and get trapped after the seas come in…
When seeking out Wakae Island the first thing that you’ll come across is the stone stele pictured above. Situated atop a large boulder, this monument was erected in 1924 by the Kamakura Youth Club to celebrate the history of Japan’s first man-made island. The text, written in March 1924 in old-fashioned Japanese, reads as follows:
“Waka is the former name of today’s Zaimokuza. This place used to be a harbor where timber was collected and shipped and, for this reason, the town’s name changed soon to the present one.
Wakaejima was an embankment built to avoid the destruction by the waves of Waka’s harbor. 768 years ago, a priest named Oamidabutsu asked permission for its building and, with the support of Moritsuna, work was started on July 15 and ended on August 9.“
— The Kamakura Youth Club

Just beyond the stone stele in the bay you’ll see a mound of rubble that was once the main part of Wakae Island. Note that on its northern side there used to be a handful of pillars that were used to moor ships against the strong southerly winds during port calls. Unfortunately however, only the one pictured above remains after the harbor ceased being used and fell into disrepair in the late 19th century. Usually it impossible to reach this part of Wakae Island on foot except for in rare cases of extremely low tides.
After taking in what’s left of the rubble, look right behind the boulder with the stele and you’ll see an unassuming staircase leading up from the beach. As the lower ground is almost always water locked, this will serve as your path to the next section of the Wakae Island remains. After you ascend the staircase, head straight towards the Riviera Zushi Marina housing complex until you see some hidden steps on your right. Be careful with your footing though, especially if it’s been raining. The footholds can be pretty dangerous if you’re not cautious. This place wasn’t exactly made to be a tourist destination after all…

After making your way down the final few steps you’ll come across the rocks picture above that seeming jut out into the ocean. This was once the location that the section of Wakae Island mentioned above connects with the mainland. If you look closely enough, you can still make out the contours of the man-made island. Be sure to also note the numerous stones that litter the seabed; these are actually the base materials from which Wakae Island was originally constructed that have been tossed about the waves. This whole area is covered in green sea slime though so be very careful not to end up in the drink!
Other Nearby Attractions

As I don’t expect anyone to make the journey all the way to Kamakura just to see the remains of an 800 year old island, here are some other cool spots you can check out in the immediate vicinity:
- Komyo-ji
This Jodo sect Buddhist temple is Kamakura’s only major temple that is located near the ocean. It is part of a group of 18 temples known as the “Kantō Jūhachi Danrin” that was established by Tokugawa Ieyasu. The site has always enjoyed patronage by Japan’s historical elite and is the only Kamakura temple to have the privilege of being the funeral spot for a daimyo warlord. In addition to being found near the sea, Komyo-ji is notable for having a very large sanmon (meaning second gate) and a formidable rock garden. Lastly the temple is also home to a special crypt run by a group of volunteers that houses the ashes of pets and other animal. - Mandarado Yagura
Unlike with the above recommendation, this alternative is not for the faint of heart and is quite the adventure even for the most experienced of hikers. Known as the Mandarado Yagura, this eerie spot is a collection of centuries-old tombs in the hills of Kamakura. Getting there is no simple task though. The trek will take you across ancient trade routes into the old capital with passes through the mountains that are barely wide enough to fit through. Nevertheless, for those really looking to get an authentic, off the beaten path experience, this is not something to pass up (especially considering how close it is to Wakae Island).
Until next time travelers…