Onrai square was on the planet Seoul 5.
Dwarfed by towering structures surrounding it, a lone statue of the Mother Goddess Onrai stood in the center.
The statue hid entrance to the control room of Seoul 5 which contained three crystals that powered the world. When Han Solo visited the world in 4 ABY, he discovered the control room but ended up unleashing the power stored with the crystals. The subsequent explosion destroyed not only the statue and square, but much of the planet also.