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Why are Triangle-Shaped Onigiri Common?

Onigiri, the Japanese soul food, is called by many names such as omusubi or nigirimeshi, and comes in various shapes such as triangular, round, and bale-shaped. What shape do you think the world's oldest rice ball was? - The answer is an isosceles triangle.

In 1987, Japan's oldest onigiri was discovered at a Yayoi period site called the Chanobatake site in Sugitani in Ishikawa prefecture. The fossilized onigiri was found to be about 2,000 years old, which is the beginning of rice cultivation in the Yayoi period (2000 years ago). This means that onigiri were born shortly after rice cultivation began.The fossil was a lump of steamed rice that had turned black. The reason why they knew it was not just rice, but an onigiri, was because it had the fingerprints of the person who made it. It was triangular in shape, strictly speaking, like a triangular pyramid. In fact, it is said that it was made to resemble a mountain.

The Actual Onigiri Fossil

In ancient times, mountains were objects of faith for people. It is believed that people made onigiri in the likeness of mountains, which were like gods. Since the onigiri was found in a charred state, it is believed that it was prepared as an offering rather than for eating. Since ancient times, it has been believed that gods are found in high places, and the high places of those days were mountains. It was believed that the power of the gods would dwell in the shape of a mountain, that is, the shape of the place where the gods were located. This is why the onigiri as offerings were made in the shape of a triangular mountain. Therefore, the triangle is the shape of God. What developed into today's onigiri were made in the Heian period (794-1185) and were called tonjiki. They were oval-shaped, weighed 1.3 lbs/600 g, and were the equivalent of four cups of rice. The difference from today's onigiri is that tonjiki were stickier as they were made of glutinous rice. Tonjiki are said to have appeared in The Tale of Genji by Murasaki Shikibu and were served to officials at ceremonies and banquets during the Heian period.


It was not until the end of the Kamakura period (1185-1333), around 1300, that they began to be made with ordinary rice as we know them today. In the Sengoku or Warring States period (1467-1615), ume pickled plums, salt, and miso were added to preserve the food as a valuable food for soldiers during warfare. Hiroshige Utagawa's Tokaido Goju-san-tsugi Saiken-zue Fujisawa depicts travelers on their way to Kompira eating triangular onigiri. It is said that onigiri became popular as a portable food during the Edo period (1603-1867), when the warring states of Japan ended and the highways were improved.

Tokaido Goju-san-tsugi Saiken-zue Fujisawa

As mentioned above, onigiri sold in Japan nowadays are called by various names and come in a variety of shapes. However, the most major shape is the triangular one, which has the same shape as the original onigiri and Maido's onigiri. This is because they are flat and stable at the bottom, making them easy to line up and difficult to fall over. Why not try making onigiri, which are easy to cook and delicious, simply by mixing the ingredients with rice and wrapping?


There is a lot of food items, housewares, stationery, and gifts available at the store and our online store, Maido! Kairashi Shop, where you can place your order for shipping or store pickup! Happy shopping. :)


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