St. Patrick's Cathedral is the seat of the archbishop of the Roman Catholic Archdiocese of New York. It is an example of the decorated and geometric style of Gothic ecclesiastical architecture which prevailed in Europe from 1275 to 1400. The cathedral is almost an expression of Irish life in the city. Seated across from Rockefeller Center on 50th Street and 5th Avenue in New York City, St. Patrick's Cathedral is the largest Gothic Catholic Church in the United States. The intention of Archbishop John Joseph Hughes to erect a new cathedral replacing the Old St. Patrick's on Mott Street - used today as a parish church in New York – in 1850 made way for the present St. Patrick's Cathedral. Designed by James Renwick, Jr., the church took more than 20 years to complete. Though it had its first cornerstone laid on Aug 15, 1858, work was temporarily halted during the American Civil War. Work commenced again in 1865, and the church was finally completed in 1879. The cathedral was dedicated in May 1879. Towers on the west front were added in 1888, and an addition on the east side, including a Lady Chapel designed by Charles Mathews, was completed in 1901. The cathedral was renovated between 1927 and 1931, when the great organ was installed and the sanctuary enlarged. At present, the Cathedral is noted for its purity of style, originality of design, harmony of proportions, and the beauty of its material and workmanship. Built of white marble quarried in New York and Massachusetts, St. Patrick's exterior is 405 feet long and 274 feet wide, and has a seating capacity of about 2,500. Constructed in Neo-Gothic style, the cathedral boasts 12 side chapels, a chime of 19 bells, the rose stained glass window reaching 26 feet across, the giant pipe organ with more than 7,300 pipes, and the twin spires at 330 feet in height. The canopy over the main altar is solid bronze. The Pieta is three times larger than the Michelangelo's Pieta. The St. Elizabeth Altar (designed by Paolo Medici of Rome), the St. Michael and St. Louis Altar (designed by Tiffany and Company), and the Rose Window (designed by Charles Connick) are other eye-catching sights inside the church. The Cathedral was visited by Popes Paul VI (1964) and John Paul II (1979). It also holds the burials of eight deceased Archbishops of New York, the Blessed Pierre Toussaint - who paid for the reconstruction of old St. Peter's Church, and the Archbishop Fulton Sheen. One can experience a similar atmosphere of beauty and peace of the medieval cathedrals of Europe, while walking into St. Patrick's Cathedral. Guided tours are available by appointment.