In October 1927, rock carvings were discovered on stone walls inside a hill in Fugoppe in the town of Yoichi, by a railroad worker who dug a path through it.
Nishida Shōzō, a professor at the Otaru College of Commerce (小樽高等商業学校), called these carvings the "Fugoppe ancient characters", forming a pair with the "Temiya ancient characters" and associating them with the Tsushima characters and old Turkic alphabet.
However, the ethnic Ainu folk researcher Hokuto Iboshi argued that the "deformed letters" were instead more recent forgeries, citing their lack of weathering compared to those at Temiya Cave.

Tatsuo Sōma opined that these carvings, like those at Temiya Cave, were made by people driven from the northeast of Honshū.
He interpreted their meaning as "Cross the sea and subjugate Suzu.
Destroy your enemies and slaughter the brutes."

In 1950, further rock art was discovered in Fugoppe Cave in the same town.
These were confirmed, like those at Temiya Cave, to be relics of the continued Jōmon period, and designated as national treasures in 1953.
These carvings, like those at Temiya Cave, are sometimes referred to as "ancient characters".

Tatsuo Sōma considered these too as made by the same group that created the carvings at Temiya and at the 1927 Fugoppe discovery.
Part of his translation is as follows:
Our prosperous lands of Unoke and Kaga have been stolen by our enemies.
Destroy, destroy, destroy our enemies, destroy them completely, smash their castle gates, smash their storehouse gates, one after the other, and thoroughly kill them all.

— Sōma, Tatsuo.
 解読日本古代文字 [Reading Japan's Ancient Scripts] (in Japanese).
p. 40.

Kaga, Nono.
Attack and defeat the brutes, o gods.

Strike at Cape Shaku in Suzu, and the eastern seashore of  Kanō; pierce through the belt of Ouchi that unites the western shores of Hakui and Wajima and Noto, great gods.

Here swear we, the people of Unoke and Togi.

Our king will sit again at Suzu.

— Sōma, Tatsuo.
 解読日本古代文字 [Reading Japan's Ancient Scripts] (in Japanese).
pp.
 42–43.

The Japan Exploration Association, chaired by Takahashi Yoshinori, contends that the inscriptions on the northern wall of Fugoppe Cave read as "iishishirai" and "kawasakanahakitsu", and mean respectively "edible beasts live here" and "freshwater fish come here".
In October 1927, rock carvings were discovered on stone walls inside a hill in Fugoppe in the town of Yoichi, by a railroad worker who dug a path through it. Nishida Shōzō, a professor at the Otaru College of Commerce (小樽高等商業学校), called these carvings the "Fugoppe ancient characters", forming a pair with the "Temiya ancient characters" and associating them with the Tsushima characters and old Turkic alphabet. However, the ethnic Ainu folk researcher Hokuto Iboshi argued that the "deformed letters" were instead more recent forgeries, citing their lack of weathering compared to those at Temiya Cave.
Tatsuo Sōma opined that these carvings, like those at Temiya Cave, were made by people driven from the northeast of Honshū. He interpreted their meaning as "Cross the sea and subjugate Suzu. Destroy your enemies and slaughter the brutes."
In 1950, further rock art was discovered in Fugoppe Cave in the same town. These were confirmed, like those at Temiya Cave, to be relics of the continued Jōmon period, and designated as national treasures in 1953. These carvings, like those at Temiya Cave, are sometimes referred to as "ancient characters".
Tatsuo Sōma considered these too as made by the same group that created the carvings at Temiya and at the 1927 Fugoppe discovery. Part of his translation is as follows:
Our prosperous lands of Unoke and Kaga have been stolen by our enemies. Destroy, destroy, destroy our enemies, destroy them completely, smash their castle gates, smash their storehouse gates, one after the other, and thoroughly kill them all.
— Sōma, Tatsuo.  解読日本古代文字 [Reading Japan's Ancient Scripts] (in Japanese). p. 40.
Kaga, Nono. Attack and defeat the brutes, o gods.
Strike at Cape Shaku in Suzu, and the eastern seashore of  Kanō; pierce through the belt of Ouchi that unites the western shores of Hakui and Wajima and Noto, great gods.
Here swear we, the people of Unoke and Togi.
Our king will sit again at Suzu.
— Sōma, Tatsuo.  解読日本古代文字 [Reading Japan's Ancient Scripts] (in Japanese). pp. 42–43.
The Japan Exploration Association, chaired by Takahashi Yoshinori, contends that the inscriptions on the northern wall of Fugoppe Cave read as "iishishirai" and "kawasakanahakitsu", and mean respectively "edible beasts live here" and "freshwater fish come here".
Hokkaido characters