As soon as my husband started building an iwaburo rock bath in our house, curious neighbors poked their heads in and asked, “When are we going to eat udon?” This is local parlance for: “When will the bath be finished?”

Japanese is said to be a vague language and thus difficult for foreigners to understand, but this was rather extraordinary. Why such a strange way to ask when a bath will be completed?!

This unusual pairing, I soon learned, can be traced all the way back to Shikoku, one of Japan’s four main islands, and an island famous for its udon noodles. Kagawa Prefecture, known as udonken (the udon prefecture) is particularly well-known for its delicious thick, starchy noodles. And we can thank Kagawa for a very strange custom: that of eating udon while sitting in a new bathtub!

Now, you probably want to know why they would do such a thing. And why udon? Wouldn’t beer and peanuts be more logical? Or, if you’re going to celebrate a new bathtub, why not go all out and have a pig roast in there? Our intrepid bathing reporter tells you why and oh, so much more about Japanese baths.

When my benriyasan (handyman) husband started building the rock bath in our house on Shiraishi Island, we had no idea about this custom. We were just happily building something from scratch.

The rocks themselves we collected from the beach on the backside of the island, where they had been washed smooth by decades of waves.


These were used for the walls of the bath area.

▼The shower area, where you clean yourself before getting into a Japanese bath.


The stone for the tub itself was imported from Sweden.

▼Toyoshima-san, a stone-cutter on the island, cut and polished the rock panels for us.IMG_1845

We procured a large slab of a 100-year old cedar tree from the temple when they were renovating and used it as the vanity.

▼This recycled piece of wood is 8cm thick and 60cm wide.


It  took a year to complete, so you can imagine how many times people asked, “When are we going to eat udon?” It was only when the bath was almost finished that we realized the gravity of the situation: We’d be treating the entire neighborhood to a bath! With noodles!

And why udon? Apparently, due to the linear extent of udon noodles (as opposed to, say, bean sprouts), their length is said to represent long life. Therefore, if you eat these protracted noodles, you will also have a long life. Soaking in a hot bath before going to bed has long been a tradition in Japan, which is also considered healthy. So it’s only logical that by combining these two activities, eating noodles in the bath, is believed to encourage a prosperous family and household that will never, presumably, run out of starch.

But eating noodles while bathing in a new bathtub is a Kagawa tradition. Why would Shiraishi Island, a tiny island in the Inland Sea–with 92 people named Amano, and 570 residents, all of whom use pit toilets–have to do with Shikoku? Afterall, Shiraishi Island is part of Okayama Prefecture, a part of Honshu, not Shikoku.

It turns out that Okayama is an exception. The Kagawa-born custom surely must have come from there, but no one is sure how. But this seaman’s map may provide a clue.

▼At the bottom of the map is Sanagi Island, an island off Shikoku, and part of Kagawa Prefecture. If you follow the island chain, you’ll come to Shiraishi Island, the third island up. If you continue island hopping, you’ll eventually hit Kasaoka City, Okayama Prefecture on Honshu.


While doing research on all this, I also found out that our neighborhood bath soiree was about to get a lot more complicated.

It turns out that Kasaoka has put its own spin on the Kagawa tradition.  The custom here was to boil the udon noodles inside a goemonburo bath and then eat them straight from the bath (as opposed to sitting in the bath and eating a bowl of noodles). After indulging in the noodles, people would then bathe in the noodle water! You’d really have to love udon to actually bathe in the aftermath.

So, now you’re probably wondering, What’s a goemonburo?

A goemonburo is an old Japanese-style bath, usually set into concrete, and designed for one person to sit inside it at a time. It is made of cast iron and is heated by a fire underneath the bath.

▼An old Japanese-style goemonburo bath


In the old days, not everyone could afford to have a bath in their house. And some places, such as Shiraishi Island, never had a public bath, called a sento. So those who were lucky enough to have a goemonburo shared it with their neighbors, who would take a bath in turn after the owners did (washing off first before getting in, of course). This was called moraiburo (receiving a bath from someone else).

The baths were located in an attachment to the house so that they were easily accessible to neighbors.

▼In this photo, taken on Shiraishi Island, you can see the brick kiln outside where the fire was lit to heat the bath. Usually there would be a chimney too, but this one is no longer in use.


The fist time a brand new bath was filled, and while it was still clean, the owners would take advantage of the large cauldron and boil udon for everyone in the neighborhood. So even now, whenever anyone builds a new bath, they invite all the neighbors over for udon.

I asked the islanders if there was anyone still using a goemonburo, but everyone said they’d been replaced by stainless steel bathtubs.

▼Stainless steel tubs are a little roomier.

stainless steel bath

But there are still plenty of old cast-iron goemonburo baths on the island. But as they were replaced with new, stainless steel ones, people used the old baths for other purposes.

▼Such as to burn rubbish in


▼Or store things in


▼Or to guard your laundry poles


▼Or just to have something hanging out in the garden, like the Western version of the garden gnome.

cast iron tub

▼This one has been abandoned. Since it is upside down, you can see the drain that was used to let out the bath water.


But I know some people on this island still kindle fire to heat their baths. Wouldn’t they still be using a goemonburo? I decided to find out.

First, I went to visit Nakagawa-san.

▼Nakagawa-san has a wood-burning furnace outside her house to heat her bath.


But she had replaced her goemonburo with a stainless steel bathtub. She told me it takes 40 minutes to heat the bath in the wintertime. So why didn’t she replace the wood-burning furnace with a gas water heater? “Because I’m used to this,” she said, smiling.

Then I visited Masashi-san who was still burning wood to heat his bath too.


But he had replaced his goemonburo with a ceramic bathtub. Masashi-san said the goemonburo is the healthiest way to bathe because it produces uniform heat from all sides. He still heats his new ceramic vessel with wood because he prefers heat that comes from the walls of the bath itself, rather than from the hot water itself. Heated water also gets cold fast, he pointed out.

I was surprised to see that even a recently renovated house on the island was also still using this method.

▼This house was recently renovated


▼But if you look closely, you’ll notice a chimney in the back


▼And a modern Chofu oven for burning wood.


▼The kanji on the side of the drum, furogama, identifies the oven as one used for heating a bath.


The islanders were right. Although some people were still using wood to heat their baths, no one was still using the old Japanese-style goemonburo bath.

But I still had a hankering to see a real one. Having exhausted most of my resources, I had to rely on the only one I had left: intuition. Watch this short video to see what I found!


Now, back to our own bath and the udon party we were about to throw. The time had finally come when our iwaburo rock bath was ready!


▼The garden the bath looks out on


Well, not quite. The bath had yet to pass inspection by the cat.

▼Everything was thoroughly sniffed and investigated


▼Even the garden was inspected


▼For a while there, we were worried it wouldn’t pass feline grooming standards



▼But in the end, she gave her approval!


Now it was time to eat udon!

Since we were the hosts and the only people who had never attended such an udon party before, we had no idea what we were supposed to do. How does one make a bathful (240 liters/63 gallons) of udon? We also worried that our bath water, filled by a natural gas heater, would never get hot enough to boil the noodles.

So we were ecstatic when someone conveniently revealed the modern version of this ancient tradition by saying, “Just buy instant noodles!” On the night of the great udon bathing event, the neighbors arrived bringing sake, wine, and six-packs of beer. I’d fill each person’s instant noodle cup with hot water from the kettle and they’d go off to take a bath while the rest waited their turn between swigs of alcohol and general merriment.

people eating udon in bath

It was just like old times waiting for the neighbor’s goemonburo!

Photos: Amy Chavez/RocketNews24