In his architectural works Michelangelo defied the conventions of his time. His Laurentian Library (c.1520), designed for the book storage purposes of Pope Leo X, was memorable for its mixture of mannerist architecture; it demonstrates Michelangelo's free approach to structural form. The Capitoline Square, designed by Michelangelo during the same period, was located on Rome's Capitoline Hill. Its shape, more a rhomboid than a square, was intended to counteract the effects of perspective. At its center was a statue of Marcus Aurelius. From 1540 to 1550 Michelangelo redesigned St. Peter's Church in Rome, completing only the dome and four columns for its base before his death.