Bernini's first work at St. Peter's Basilica was designing the baldacchino, a 30-meter tall bronze pavilion above the altar. Its design was based on ciborium that are used in Roman churches to create a holy space above the altar during Eucharist. Bernini's concept was different, taking inspiration from the baldachin carried above the pope and eight ancient columns in the old basilica with a twisted barley-sugar shape symbolizing the column Jesus was bound to. Based on this, Bernini created four large twisted bronze columns decorated with olive leaves and bees representing Pope Urban.