Princess Aiko, the only child of Emperor Naruhito and Empress Masako, traveled to Mie Prefecture this weekend to take part in centuries-old Shinto ceremonies preparing for the next rebuilding of the Grand Shrines of Ise — a ritual reconstruction that has repeated every 20 years for more than 1,300 years.

She arrived on Friday, August 1, visiting a facility where timber for the upcoming shrine reconstruction is prepared and cut (Asahi Shimbun). On Saturday, she observed the Kawabiki ceremony, in which a large crowd hauls timber down a river as part of the preparations. Then she joined local residents herself for the Okihiki ceremony, pulling a rope in a white happi coat — a traditional festival jacket — to drag sacred timber into the inner shrine grounds, chanting in time with the crowd (Town & Country; Nippon.com).

The Grand Shrines of Ise, or Ise Jingu, are the most sacred site in Shinto, Japan's indigenous religion. The Shikinen Sengu is the ritual in which the shrine buildings are dismantled and rebuilt from scratch every two decades, using freshly harvested timber and traditional techniques. The next full reconstruction is scheduled for 2033, and the ceremonies Aiko attended are early steps in that long preparation (Town & Country; National Geographic).

This was Aiko's third pilgrimage to Ise Jingu and her first in two years. She previously made a solo trip there in 2024 to report her university graduation and her new role at the Japan Red Cross to the imperial ancestral deity — a customary step for members of the imperial family at personal milestones (Japan Forward). Emperor Naruhito noted at his 2025 birthday press conference that Aiko had begun traveling alone for official duties, including worship at Ise Jingu and Nara (Imperial Household Agency).

The visit comes weeks after Japan's Parliament passed a new Imperial House Law in July, set to take effect on October 24, 2026. The law allows male descendants from 11 former imperial family branches to be adopted into the Imperial Family, and permits female members to keep their royal status after marriage — a change from the previous rule that stripped princesses of their title upon wedding a commoner.

But the law does not open the line of succession to women. Princess Aiko remains ineligible to inherit the Chrysanthemum Throne, as does every other woman in the family. Adopted men would have no succession rights themselves, though sons born to them after adoption would enter the line.

Japan's throne can currently pass to only three people: Crown Prince Fumihito, 60, the emperor's younger brother; Prince Hisahito, 19, Fumihito's son; and Prince Hitachi, 90, the emperor's uncle (Town & Country).

A Nikkei and TV Tokyo poll conducted after the law passed found more than 80% of respondents in favor of female emperors. The Imperial House Law itself left that question untouched.

The contrast is sharp: a princess standing shoulder to shoulder with villagers, hauling sacred timber for a shrine rebuilt the same way for 1,300 years — while a law written this summer confirms she cannot follow her father onto the throne. The ceremony reaches back centuries. The succession debate is happening right now.