Sanuki no Suke's Diary: Note on the Ice (Kori 氷) and Icehouses (Himuro 氷室)

 

In the mid-seventh month of the lunar calendar (mid-August in the modern calendar), ice was an extraordinary luxury, practically exclusive to the Emperor and high-ranking aristocrats. Without modern refrigeration, obtaining ice in the sweltering Kyoto summer required a sophisticated system of winter harvesting, storage, and logistical transport managed by the Imperial Office of Water (Mondo-no-tsukasa 主水司).

During the coldest winter months, thick ice was harvested from frozen ponds and rivers, then stored in semi-subterranean icehouses (himuro 氷室) packed with straw and thatch for insulation. According to the 10th-century legal code Engishiki (延喜式), six official icehouses were established in Yamashiro Province (present-day Kyoto) to supply the Imperial Court. Most were strategically hidden in the cool, elevated valleys north of the capital:

Kurusunono & Tsusaka (Nagasaka) Icehouses (栗栖野・土坂氷室): Located in modern-day Nishigamo-Himuro-cho, Kita Ward. Situated in a mountain basin at an elevation of about 380 meters beyond the Kyōmi Pass (north of Kinkaku-ji and Takagamine), this was the primary and closest major icehouse complex. Today, visitors can still explore the historical site (Himuro-ato, a designated historic site of Kyoto) and visit Himuro Shrine (氷室神社), which is dedicated to the deity of ice.

Iwasaki Icehouse (石前氷室): Located near the Kinugasa area just north of Kinkaku-ji (modern-day Kinugasa-Himuro-cho, Kita Ward).

Ono Icehouse (小野氷室): Nestled in the mountains along the Takano River near Yase and Ohara, southeast of Kurama (modern-day Kamitakano-Himuro-yama, Sakyo Ward).

Tokuoka Icehouse (徳岡氷室): Located in the Omuro district north of Ninnaji Temple (modern-day Omuro-Sumiyoshi-yama, Ukyo Ward).

Sakakibara Icehouse (賢木原氷室): Situated in the hills west of the Katsura River (modern-day Katagihara, Nishikyo Ward).

Transported under cover of night to prevent melting, this precious ice arrived at the palace as a rare comfort for the gravely ill Emperor Horikawa. Understanding this historical background illuminates the deep devotion of the court attendants who presented it in a metal bowl to soothe his high fever, as well as the poignant image of the weakened emperor attempting to carve it himself.