The Japanese City Where Food Is Steamed in Hell

Kannawa is a small neighborhood in Beppu City. There are dramatic, billowing clouds from hot-spring vents. The streets are like a sauna, with steam rising from drain pipes and cracks in the road.

Beppu has the highest concentration of hot springs in Japan, with more than 100,000 liters of water gushing from its hot springs each minute. The city is known for its hot springs, as well as being a bather's paradise.

There are large, box-like chambers made of brick or concrete with rows of wooden lids on top. These are called jigoku-gama, orhell ovens, and are usually made of stone or brick and reinforced with concrete. To use one, you usually twist a valve to release massive jets of super-hot, mineral-rich geothermal steam, which also enhances food with a subtle kiss of sodium chloride.

A basket of freshly-caught prawns and mussels would be a good choice, as would seasonal vegetables, bamboo leaf, and sake-marinated sea bream. Place your ingredients in a basket, lower it into the oven, cover it with a lid, and let the boiling-hot steam work its magic. When you get the basket, you will get food that tastes like the best version of itself, because the steam brings out its subtle flavors.

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When she was a child, restaurant owner and Kannawa native Haruko Yasunami was a big fan of hell-steaming. She remembers visiting one of the local inns in the spring. She would bring a bunch of bamboo shoots from the hill near her family's house to cook in the inn's hell ovens. The traditional way to prepare bamboo shoots is to boil them several times to remove the bitterness, but steaming makes them sweet and tender.

To thank them, we would give them bamboo shoots. They were like, "please, no more!"

It's possible to cook with steam in volcanic regions across the world. References to cooking in Japan date back as far as the eighth century. The Edo period brought an influx of tourists to Beppu's springs.

Thanks to the development of a well-maintained nationwide road network, people across social classes were able to travel on the pretext of undertaking religious pilgrimages, and those who had heard of the hot springs of Kannawa would occasionally do so.

Visitors to the area were taken with hell-steaming when they saw the hot springs that were supposed to be used to recuperate and soak away your ailments for a few weeks. The 19th-century illustrated guide Tsurumi Shichit chronicled how villagers living near the springs steamed food in a wild manner.

The book included recipes for dishes such as karukan, which is a sweet made from rice flour, sugar, and yam, and Ryukyu sweet potatoes, which is a sweet made from yam and sugar.

Hell-steaming remained rudimentary until the early 1900s, with the exception of some advanced Meiji-period steam chambers. In his memoirs of traveling around Japan between 1901 and 1906, the British photographer Herbert George Ponting wrote about the ubiquity of hell-steaming in Kannawa, where steam can be found almost anywhere.

Meiji-period records show that children pushed sticks of bamboo into the ground to create their own vents, and that they snacked on freshly- picked soybeans from the fields.

During the postwar years, children would leave some sweet potatoes near steam rising through cracks in the ground.

The beginning of Kannawa as a major tourist destination was marked by the charging of admission fees to Beppu's hells. There was a crop of businesses around Kannawa in the late 1920s. Budget travelers were able to stay in Kannawa for weeks at a time because of the low overheads and room prices. Rental rooms gave customers access to a communal kitchen with shared cooking facilities, similar to backpacker hostels, which allowed guests to mingle and befriend each other.

Hell-steaming is more of a tourist-oriented practice than it was in the past. Unless they have their own hell ovens, most local residents don't eat hell-steamed food on a daily basis. They can always use their neighbors ovens, but they might have to pay a fee to the owner.

They didn't have a concept of paying to use it back then.

In order to promote tourism in Beppu, the city opened the volunteer-run Jigoku Mushi Kobo Kannawa in April 2010. You can rent an oven for 10 to 15 minutes and steam baskets of ingredients from the center. You don't have to stay at an inn or rent a room to steam eggs.

The sale of hell-steamed purin in nearby Myōban Onsen has become popular with visitors. The treats are silky, with a gorgeously bitter caramel sauce and a hint of hot spring sulfur, but I only tried one and went home with six more. They appeal to a younger crowd and are a change from the traditional hot spring manju.

One of the most intriguing uses of hell-steaming is at the restaurant Mushi Char, which serves Chinese cuisine steamed at lower temperatures. The idea is that when cooked with steam it tastes better and retains its vitamins more readily. Chef Maeda's steamers regulate the saturation and temperature of the steam that comes from the restaurant's underground vents.

There are a few restaurants in Kannawa. Beppu has a lot of hot spring sources, but why aren't there more restaurants that are interested in cooking? Purchasing the rights to drill for one million dollars before all the construction and maintenance costs is the first thing that comes to mind when thinking of the cost of a hot spring source. Kannawa is a protected area in Beppu, and only current rights holders can replace a source if it stops working.

If there is a new hot spring source within 80 meters, you can drill it. The Kannawa area has more or less maxed out on hot spring sources.

The volume and temperature of steam and water across Beppu's 2,300 hot springs have taken a noticeable dip since 2019. Tsutsumi, a local tourism officer working with Savor Japan, thinks the increased use of geothermal resources in recent years may be a contributing factor.

Jigoku Mushi Kobo Kannawa was forced to temporarily close its operations for two months in the middle of the year because the steam wasn't hot enough for its normal operations. Businesses are worried about the effects on their hot springs. Maeda's low-temperature operations are unaffected by this.

When the steam temperature dropped to 70 degrees, there was a lot of panic and concern.

Tsutsumi says it would be interesting if the staff could adapt to lower steam temperatures, but not everyone is as knowledgeable as Maeda is.

For the time being, hell-steaming isn't going anywhere. Visitors to Beppu can sample all kinds of hell-steamed sweet treats, cook at the hell ovens of Kannawa, or eat a multi-course hell-steamed dinner at Mushi Char. There is a taste of heaven in this kitchen.

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