There's an ancient shrine called Kanda Myojin in the Soto Kanda district of Chiyoda City in central Tokyo. Just to the left of the shrine's torii gate you'll find Ama-zaké-dokoro Amano-ya, a store that opened its doors more than 160 years ago. It sells a sweet rice wine called ama-zaké, which is made by fermenting rice with koji yeast. The sweet taste of ama-zaké has been favored by working men and women since around the 17th century.

The fifth-generation owner of the store, Amano Yaichi, told me, "When the store first opened they produced malted rice called koji. As a side business, they used the koji to make ama-zaké rice wine and served it on the premises."

Saké cannot be made without koji malt. Koji is prepared by mixing koji yeast (a kind of mold) with steamed rice or another grain, then letting the yeast grow. At Amano-ya, the koji is made in a cellar, just as it was when the store was founded.

The cellar is about 30 square meters in area, and the floor lies about 6 meters below ground level. Steamed rice is seeded with koji yeast, then left in the cellar for four days to let the yeast spread through the rice. The cellar provides an ideal environment for fermentation, and the result is an excellent malt. Yaichi explained, "The cellar walls keep the humidity at the optimum level for the koji. Also, we heat the cellar to 30°c to start with, and the walls are able to keep it at that temperature."

Amano-ya is now the only place in Japan still producing koji rice malt the old way, in a cellar.

The Osarizawa mine is located in the city of Kazuno, Akita Prefecture. It was one of Japan's most productive copper mines, but it closed in 1978. The old shafts measure a total of 800 km in length. A theme park called Mineland Osarizawa was constructed in an abandoned 800-meter shaft, to make Japan's biggest gallery for shooting games. The shaft is now a fantasy universe where players ride electric carts and shoot down aliens with laser guns. One "shooting adventure" around the shaft takes 20 minutes.

Nara Akiko works for Osarizawa Kanko, the company operating the theme park. "It's a competitive game, based on a point system. The thrill brings people back time after time."

Nara joined the company after graduating from junior college. Her grandfather used to work in the mine, and this is one reason why she decided to work there. "My father worked in the mine next to this one, and that's also why I wanted a mine-related job. That makes three generations of us working underground."

Part of the shaft has been kept in its original state, and is now a mining museum called Kozan Rekishi no Michi. When talking to people who come for the shooting game, Nara always suggests they take in the museum as well. "The mine shafts are a local cultural asset well worth experiencing."