Kamakura’s Wakaejima

Solving the Mystery of Ancient Engineering Remnants

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…