Urban VIII Barberini, who was Pope from 1623 to 1644, would be in charge of commissioning a young Bernini to decorate much of the interior of St. Peter's, including the notable Baldacchino. Placed above the tomb of St. Peter, the Baldacchino is made of bronze as well as other materials. There are four spiraling columns, the rotary motion expresses an upward feeling of movement.
The entire structure is covered with papal symbolism, for example the Barberini bees. The structure stands at 100 feet and with its mix of natural, architectural, and decorative it acts as a mediator between the pilgrim and the vastness of St. Peter's. Bernini, who went on to be the most important sculptor of the Baroque period, highlights his variety of skills. By considering architecture and sculpture, he produces a continuum through space where the viewer is involved in activating the scene.
At the altar behind the Baldacchino is Bernini's Cathedra Petri (Chair of Peter), is a reliquary holding a wooden chair that is said to have belonged to St. Peter. The sculpture backing the throne is an example of how Bernini combined sculpture with architecture; the sculptural beams of light and the stained glass evoke the harmonious relationship.