After dragging her through multiple atomic bomb ruined schools and two days of visiting bomb-centric Hiroshima museums I took my lightly traumatized wife to an island full of bunnies to recover. The island had beautiful, natural scenery and uncountable therapeutic bunnies for her to recuperate with, while I took in the island’s other primary attraction, the poison gas museum and poison gas plant ruins that the whole resort is built around.

He’s here to look at anytime you feel the need to take a break. Also, they all have kind of messed up ears, I think there’s some kind of feral bunny fight club going on.

Then she was traumatized all over again.

She knew what she was getting into when she married me.

Okunoshima’s military history goes back to the 1890s when the Geiyo forts were built on the Seto Inland Sea to defend against invasion. Three batteries with 22 cannons were installed on Okunoshima in 1902 and ready to defend against Russian incursion during the Russo-Japanese War, though the threat never materialized.

The Imperial Japanese Army decided to build a poison gas plant on the island in 1927. Okunoshima was chosen for its seclusion- work could be conducted secretly and if there was an accident it would be easy to contain in such an isolated place. The locals for their part where not made aware of what the new facility was and celebrated the opening of the Second Tokyo Military Arsenal Firearm Depot Tadanoumi Munitions Plant (later Second Tokyo Military Arsenal Tadanoumi Munitions Plant) on May 19, 1929.

Now a poison gas plant, Okunoshima quietly began disappearing from maps and the local population evacuated. Secrecy was its first and last line of defense.

The plant primarily produced mustard gas (Yperite/Iperite) and Lewisite as well as other deadly and non-deadly gases and a pesticide. Beside manufacturing gas it also produced balloon bombs and chemical hand grenades, though chemical shells were filled off-island. At its wartime peak 5,000 workers were employed and more than 1,200 tons of gas was produced annually.

This photograph in the Poison Gas Museum depicts the production of Lewisite.

With Japan’s invasion of China came the use of chemical and biological weapons against the Chinese. The use of poison gas was brought before the League of Nations and evidence produced, but Japan denied it had used gas until 1984. As of 2017, the Japanese government is still working with China to remove the more than 700,000 chemical bombs it left behind.

After the war, the island was taken over by the U.S. Army which oversaw the destruction of Japan’s gas stockpile. It was also used as a munitions depot by the U.S. during the Korean War.

We arrived via ferry from Takehara, the only legal way to and from the island, and were quickly bussed to the south-side hotel. This is the one developed area of the island and it felt like a bit like a third-world tourist attraction with its modest appearance, dead lawn and palm trees. Endless bunnies dotted the landscape. Signs on the ship and shore warn to not personally engage with the bunnies in any way… but that’s not how people work when confronted with cute things.

One of our first sights upon arrival was watching the hotel staff, decked out in bunny ears, waving good bye to a bus full of visitors headed back to the pier. It was my first brush with the island’s eccentricity.

After that bus left there were few people wandering around. Other than a large group of high schoolers on a field trip, the island was rather sparsely populated during my visit in April 2018 giving the area an almost but not quite abandoned feeling.

The hotel actually began in the old laboratory that’s now behind it and guests originally stayed in poison gas plant facilities before the hotel proper was erected, though it looks like the old labs are still used for other purposes. Dr. Moreau comes to mind, but I’m sure it’s nothing like that. Then again… who the hell reuses a poison gas plant as a resort?

The new exists in harmony with the old, tennis courts built between poison gas storehouse ruins and a restroom building is even built in front of the ruins of World War II-era poison gas plant restrooms. It’s clearly marked. Cool but kind of weird.

Just beside the hotel, where the big-name, high-end chain restaurant usually is in most resorts, is the Poison Gas Museum. This small but complete museum wants visitors to know the unvarnished history of what happened here and carries the hope that it never happens again. All the important points are dual language, English and Japanese, but individual artifacts are not. Most are fairly easy to understand based on appearance. It’s here that the island’s sad history is played out.

Most of the artifacts and information not directly about the island’s history relate to the plant workers and their working conditions. This was not a safe place to work. They worked 13 hour shifts and production methods, just like protective measures, where crude and much was done by hand. Safety standards were lax, some gases could penetrate their protective garments no matter what and the solution to dealing with workers getting sick from the gas they were working with was to transfer them a different department handling a different gas. Pretty much every former employee developed respiratory issues that plagued them for the rest of their lives.

The displayed artifacts were fascinating as so few museums have a room dedicated to chemical weapons and their production. The standouts where the chemical mortar rounds, a Lewisite still, and a fully-clothed mannequin in chemical protective gear, which like anyone wearing a gas mask, is creepy. It must have taken workers some getting used to, seeing these masked figures and being one as well.

The museum’s second room graphically details, with pictures, the effects of the poison gas created by this island. Graphic but not gratuitous as everything is done to illustrate just why the use of poison gas has been forbidden. There’s also a horse-mannequin covered in horse chemical protective gear, which is something I didn’t know the Japanese had used as I’d only seen pictures of such gear from the Great War.

Fully re-traumatized, my wife then spent the rest of the day sitting at the hotel and enjoying bunnies within the established rules of how one is allowed to interact with them. I took a picture of the dual language map in front of the hotel and disappeared into the jungled hills, seeking out the island’s many ruins.

Ruins are what Okunoshima should be known for. (As a travel selling point I mean.) Though most of the poison gas plant is gone, I’ve never seen so many preserved Japanese military ruins in one location. There’s three complete sets of Meiji-era gun batteries (minus guns), a gutted power plant shell, disappearing searchlight positions, gas storage everywhere and a slew of random bits from one end of Okunoshima to the other. Most of them are mapped and even have placards to explain what it is and sometimes even have pictures of what it looked like in service.

For the most part it’s easy to see as there are well-paved paths that can be biked or walked around the island’s low lands but the story changes when heading into the hills.

As I got higher, it became more of a hike through marginally-landscaped jungle. Lush and full of pleasing purple flowers, it was like the idealized jungle one sees in movies. It’s not fully tamed though and at times the trails peter out to rabbit trails leaving me to wonder if I’d gone off track then suddenly the proper trail or a clearing would appear and hey, there’s the untouched ruin of a gun battery. And are those gas tank hardstands in the jungle clearing? (Seriously, the lax safety standards are a bit unnerving.)

I wouldn’t recommend the higher elevation path to people with small children or hiking with intoxicated friends because they sometimes are partially washed out and I was just left balancing on a half-eroded ridge trail. It adds to the ‘adventurous’ feeling of the place, but not something to challenge if held down by safety concerns.

I spent a six-hour day at Okunoshima and saw everything. Moving unencumbered (by slow people or people who believe in rest) it was brisk sightseeing with just a little bit of extra effort required, which made it all the more fun, and fully doable for any able-bodied person. I had time to enjoy everything and take my time doing so.

For those with more limited schedules I’ll outline the best things to see and make some observations.

As mentioned earlier, there’s a low-land ring road around the island which hits most of the better preserved spots. Walk past the tennis courts along the broad road, or to see more minor ruins along the way walk along the backs of the tennis courts, heading north and you’ll see the various poison gas storehouses. The biggest and most imposing is the Nagaura storehouse, which is almost at the northern tip.

Nagaura Storehouse

Nagaura is where the army split open a hill from top to bottom then filled it with poison gas tanks the size of single-family homes. The burned-out concrete shell bothered me quite a bit because, like the rest of the gas tanks, it was completely unprotected from air attack. One massed B-29 air raid and the whole island would have gone up like a tinder box, probably emitting a poison gas cloud big enough to kill everyone on it.

Just past Nagaura is the northern battery complex. This is a series of gun batteries in different types of emplacements so there’s variety here and I could do everything except go inside the sunken barracks between emplacements, several of which are submerged under water.

Meiji-era coastal defense batteries from the Russo-Japanese War are all made from the same blueprints, so while they all kind of have unique features they all also kind of look the same. The two standouts for this set of batteries are the storehouses for the 12cm rapid-firing guns and the gas storage tank hard stands that were mounted in one of the 24cm battery gun pits. I’m pretty certain no other battery in Japan had that special feature installed after decommissioning.

The other two batteries are up in the hills. The central battery is up a quick but steep hike from the northern battery and the best way to see it would be to transit from there. The central battery has a few different gun mount arrangements with minimal explanation, it seems the nice Japanese & English language signs didn’t migrate to the top of the island though bunnies have for some reason. I walked alone among gun pits partially overgrown by jungle, beautiful, eerie and… wow, these little guys are adorably aggressive when they beg for food. I’m not sure if it’s eerier with or without bunnies where they really shouldn’t be. Putting bunnies in abandoned places with dark histories practically turns this into the setting for a horror novel. And then there was that high school field trip wandering about… be back in a bit, I need to go write a horror novel now.

Central Battery

Central Battery- likely the barracks and/or offices

Central Battery- likely the barracks and/or offices

Central Battery- likely the barracks and/or offices

The last battery, the southern battery, is one I only recommend if you have the time. It takes a little more work to get to and is partially covered over by sand. It’s the least visitor friendly as well as the smallest. The most interesting thing about it was seeing stumps for missing structures on the way up on a disappearing jungle trail.

Southern Battery

Continuing the island loop from the northern battery there’s a slight detour behind a man-made hill for the powder magazine. The magazine is a roof-less red brick storehouse which sticks out because it’s the only standalone red brick building on the island. Red brick was a popular, new building material during the era and so was common on military installations. They lost popularity in the 1920s when it was discovered that they don’t handle earthquakes as well as ferroconcrete.

Powder Magazine

Almost all the ruins on the map can be visited but a few have been made off-limits such as the northern searchlight station and the northern battery observation point. Not a lot of locations and seemingly for different reasons. Some look like the path is no longer safe and others have been fenced around and construction material scattered about, like work was going to be done then halted. These abandoned construction sites add to the island’s strangeness, as if just in case the bunnies didn’t pan out this is where the velociraptor pen was going to be built. (For some reason I kept thinking about Jurassic Park during my visit.)

The last stop before getting back on the ferry is the power plant area. This is the biggest ruin on the island and the one you’ve probably seen when looking up Okunoshima online. It’s a huge, gutted shell of a building that’s in the center of a cluster of other small ruins, like a ferroconcrete water tower that’s completely covered in vines. Except for the water tower the rest is behind a ‘do not cross kudasai’ fence, which one can accidentally cross when approaching from the wrong direction down a path. Don’t blame me; by time I saw this I’d already been conditioned to accept a trace of trodden dirt and light foliage as an official trail.

It’s big, but honestly after seeing the batteries and Nagaura poison gas storehouse, was not the most impressive ruin I’d seen here. After seeing this you’re back at the ferry and can head back to Honshu while pondering what you’ve just seen, the inhumane nature of man and the violence he can inflict upon him and cute bunnies. If you need assistance, Takehara City is home of Nikka Whiskey. Convenient, right?

If you have the time and stamina, I encourage you to make the hike to the observation platform on top of Okunoshima. It has a commanding view of the surrounding islands, each as green as Okunoshima itself, and the hike up is a sight-to-see unto itself as this is a very beautiful island.

If given a chance I’m not sure if I’d revisit this place. While I was on the island it was like an adventure with jungle paths leading to ruins, but looking back at the imagery and thinking on the place, I get a sense of unease I can’t quite place and it bothers me. I’ve been to a lot of battlefields and places with dark histories and they’ve not given me that, but something about Okunoshima does.

It’s probably just me. Thousands of people come to this island every year to get their bunny fix and a side of jungle scenery with crumbling concrete and rusting steel.

Other than the ferry fee, the only admission cost on the island is 100 yen for the Poison Gas Museum. The ruins are free to explore. I recommend the museum; it’s reasonable and will enhance your visit if you’ve come to learn about history instead of romping about with bunnies. The only places to buy food are in the hotel, it has a café and restaurant. The café was reasonable and I tried a Takehara specialty, a burger with a croquette along with meat, and buns made of rice.

Below is the official Okunoshima website which details travel arrangements, ferry costs and timetables:

https://www.takeharakankou.jp/en/

To read a first-hand account of life on Okunoshima read the chapter “Poison Gas Island: Nakajima Yoshimi” in Japan at War by Haruko & Theodore Cook.

And if you want even more Meiji-era gun batteries, just across the Seto Inland Sea is Imabari’s Oshima Island which has an entire island of them.

ADDRESS
Poison Gas Museum
5491 Tadanoumicho, Takehara, Hiroshima Prefecture 729-2311
0846-26-3036
http://rabbit-island.info/en/
(Please note they almost entirely ignored all the cool parts about the island having tons of ruins to focus on pests with big ears.)