An artist's concept of Saiji temple. The five-story pagoda is in the left corner in the foreground. (Provided by Kyoto department of protection for cultural assets)

KYOTO--The remains of a building that is likely a five-story pagoda were discovered at the site where Saiji temple was built at the beginning of the Heian Period (794-1185) in what is now Kyoto’s Minami Ward.

The find provides clues to uncovering what two pagodas in the ancient capital known as the “twin towers” may have looked like.

The towers likely consisted of one pagoda in Kyoto's Toji (or east) temple and the five-story pagoda at the Saiji (west) temple.

The city’s department of protection for cultural assets announced the discovery on Oct. 24.

During a dig at the Saiji temple grounds that began at the end of September, excavators found evidence of a building they believe served as the pagoda's foundation.

Nobuya Ami, a professor of archaeology at Kindai University, said chances are good the ruins are tied to the pagoda.

“The pagoda in Saiji temple is thought to be at a location directly opposite the five-story pagoda in Toji temple, so the remains are highly likely to be it,” Ami said.

On the 95-square-meter site, which is now on privately owned land, excavators discovered 12 oval-shaped holes in the ground likely made to prevent the foundation of the structure from sinking.

The holes are roughly 2 meters in diameter and 0.5 to 1.2 meters deep.

The department believes construction of the pagoda began in the late ninth century or later.

Saiji temple is believed to have been constructed to align symmetrically with the Toji temple across a straight line connecting the Rajomon gate and the Suzaku oji street in a north-south direction.

But the location of the pagoda had remained unknown.

Saiji temple was built with its companion Toji temple inside the front entrance to the walled city of Heiankyo, following the relocation of the capital in 794 from Nagaoka to the city, now called Kyoto.

According to historical records and literature of the period, Saiji temple's pagoda construction started around 882. It burned down in 1233 during the Kamakura Period (1192-1333) but was never reconstructed.