The Iconic Tower of the Sun Sculpture & Mysteries of the 4th Face—The Underground Sun

Osaka Expo ’70 Commemorative Park is well-known for its massive Tower of the Sun sculpture that welcomes visitors to the park, located in the city of Suita. But did you know it has 4 faces? Or should I say had…
There are 3 faces visible from the surface level—the Golden Mask, the Face of the Sun, and the Black Sun. But there is actually a little-known fourth sun, the Underground Sun that is shrouded in years of mystery. And you can see still it, sort of.

■The Underground Sun & how it was forgotten

▲Face #1 of Tower of the Sun, the Golden Mask

▲Face #2 of Tower of the Sun, the Face of the Sun

▲Face #3 of Tower of the Sun, the Dark Sun

There are two main reasons why the Underground Sun was essentially forgotten after the 1970 Expo, where hundreds of thousands of people must have seen it. First of all, the Underground Sun was located in the basement of the Theme Pavilion featuring the Tower of the Sun. After the expo the basement and the entire inside of the sculpture was closed to the public for many years.
Secondly, the Underground Sun, which was 3 meters tall and 11 meters wide, actually went missing during construction to fill in the basement floors of the pavilion after the Expo. The official Expo ’70 Commemorative website states, “Today, almost 50 years have passed since it was removed after the closing of the Expo, and yet it is still not known where it has gone.” Needless to say, it’s a bit of a mystery.

■The legacy of Osaka Expo, restored 50 years later

During the Osaka Expo, the artwork inside the sculpture called Tree of Life—a larger than life piece on the evolution of mankind and other animals—was extremely popular. The Underground Sun was located in the basement of this exhibition area.
The basement was then filled in, and the interior was completely closed to the public. Time passed. But renewed interest in this important piece of Osaka Expo’s legacy led to restoration work on the Tree of Life and a recreation of the lost Underground Sun. The inside of the sculpture was then reopened in 2018 using a reservation system.

▲Face #４ of Tower of the Sun, the Underground Sun

The replica Underground Sun features two hollow spaces that resemble eyes and solar prominences flowing out from either side.
The background behind the face is illuminated in gold, silver, bronze, red, and blue lights giving it an ethereal feel. Something about the experience of standing here is like viewing the prized object of worship at an ancient temple. The artist, Tarō Okamoto must have wanted to create something exuding a very primal energy representative of the origin of life.

■Entering the Tower of the Sun sculpture & how to make reservations

To get inside the tower, head around to the back of the sculpture to see the dark face of the sun and you’ll find an entrance on the right side.

▲Tower of the Sun logo at the entrance to the monument

Reservations for entering the monument can be made on the Expo ’70 Commemorative Park website (entrance fee required). When the monument first re-opened to the public it was difficult to get a reservation, but it’s easy to make reservations now.
Photography is only allowed on the first floor where the Underground Sun is located and the Tree of Life sculpture starts.
From amoebas and dinosaurs, the sculpture features 292 forms of life displayed along the trunk and branches. It is very impressive!

▲The Tree of Life sculpture inside the Tower of the Sun

Apparently during the Expo there were escalators, however now you have to walk, all the way up to the top, on stairs, to a height of 41 meters. You can also peer inside the two open cavities in the arms of the sculpture. You can also see where the inspection passages were too.

*Elevator service is available for those who cannot climb the stairs. Please confirm elevator availability at the time you make your reservation.

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