Bernini's first work at St. Peter's was to design the "baldacchino" which is like a tent or "pavilion" above the High Altar. This amazing thing is 30 metres (98 ft) tall and is probably the largest piece of bronze in the world. It stands underneath the dome and has four huge bronze twisted columns decorated with olive leaves and bees, because bees were the symbol of Pope Urban. Pope Urban had a niece that he loved very much and he got Bernini to put her face and the face of her new-born baby boy on the columns as well.