The Sakafune-ishi Stonework, Asuka

The Sakafune-ishi Stonework is a mysterious archaeological site located in Oka, Asuka Village in Nara Prefecture. The main stone is a massive granite structure measuring 5.5 meters long, approximately 2.3 meters wide, and 1 meter thick, weighing approximately 100 tons. Carved on its top surface are several dish-like indentations connected by grooves, creating a unique and enigmatic appearance. The site dates back to the era of Emperor Saimei in the 7th century, though its exact purpose remains a subject of debate among historians.

In the 1990s, stone walls were discovered on the north slope that are believed to be the remains mentioned in the Nihonshoki (Chronicles of Japan) during Emperor Saimei's reign. A major excavation in 2000 uncovered a turtle-shaped stone structure measuring 2.4 meters long and 2 meters wide, along with a coin-shaped stone structure and an elaborate water system with stone gutters and paving. The turtle-shaped stone features a hollowed basin 1.25 meters in diameter and 20 centimeters deep, with water flowing through holes carved in the head and tail. These structures were used for approximately 250 years until the Heian period and are believed to have been part of a ritual site for religious ceremonies.

Visitors can explore the main Sakafune-ishi stone situated atop a small hill surrounded by a bamboo forest, creating a tranquil atmosphere. The site offers a rare glimpse into ancient Japanese stone-working techniques and ceremonial practices. The tortoise-shaped stone structure at the foot of the hill displays cutting-edge stone processing and carving techniques from approximately 1,400 years ago, with authentic stone pavement preserved as it was in ancient times. The peaceful setting allows visitors to contemplate the mystery of these enigmatic structures while enjoying the natural surroundings.

The site is accessible by taking the Kintetsu Line from Nara Station to Asuka Station, a journey of approximately 30 minutes. From Asuka Station, take a local bus toward Oka and disembark at the Oka stop, followed by a 10-minute walk to the site. For those driving, follow Route 24 toward Asuka in Takaichi District, with parking available near the site. Parking fees are typically around 500 yen. The main Sakafune-ishi stone can be viewed free of charge, while there is a small donation requested for viewing the turtle-shaped and coin-shaped stonework, collected under the pretext of cultural property conservation.