VATICAN CITY — One of the most popular attractions of the Vatican Museums, Michelangelo’s Sistine Chapel, will be closed to the public over the next few weeks, as cardinals gather there to elect the successor of Pope Benedict XVI. But visitors will be able to find some artistic consolation by lingering in the rooms that Raphael painted in the second-floor apartment of the Pontifical palace used by Pope Julius II (and his successors until the mid-16th century), their 30-year restoration now finally complete.

Raphael, an artist and an architect, was summoned to Rome in 1508, and the four frescoed rooms where the pope conducted his business were a prized commission. The rooms were originally decorated during the reigns of Popes Alexander VI (1492-1503) and Pius III (whose papacy lasted less than a month in 1503), by renowned Renaissance artists like Piero della Francesca, Luca Signorelli and Bramantino. Julius II brought in other luminaries to complete the work before deciding to give Raphael carte blanche to start fresh.

The restoration campaign brought new insights into how Raphael worked, including how he transferred his drawings from a nearly nine-yard-wide cartoon onto the walls, the methods he used to apply plaster, how quickly he painted and the organization of his workshop. One example: A recipe Raphael invented to copy the stucco of antiquity that he saw on an underground visit to Nero’s palace buried under the Colle Oppio in Rome.“Raphael was a very adventurous artist, and continually experimented, so from this point of view these frescoes are more unique than Michelangelo’s,” said Prof. Arnold Nesselrath, delegate for the scientific department and laboratories of the Vatican Museums, and the only member of the original restoration team still involved.