Kyoto's mountain cherries reached full bloom on April 11, 1231 — day 101 of the year. Of the 838 years on record, the 239th earliest. From 812 to 1850 the average was April 15 (day 105.2). The 30 years to 1231 averaged day 105.0. Before modern weather records, the date comes from diaries and chronicles of flower-viewing parties at the imperial court, temples and shrines, gathered by Yasuyuki Aono. Data: Aono and Kazui (2008), Aono and Saito (2010), Katata (2026), via Our World in Data (CC BY 4.0). https://ourworldindata.org/grapher/date-of-the-peak-cherry-tree-blossom-in-kyoto