Nothing else in Rome quite lives up to the awe-inspiring collections of the Vatican Museums, a 15-minute walk from St. Peter’s out of the north side of Piazza San Pietro. It’s a vast treasure store of art from antiquity and the Renaissance gathered by the Roman Catholic Church throughout the centuries, filling a series of ornate papal palaces, apartments, and galleries leading to one of the world’s most beautiful buildings, the justly celebrated Sistine Chapel (considered part of the museums for admission purposes).

Note that the Vatican dress code also applies to the museums (no sleeveless blouses, no miniskirts, no shorts, no hats allowed), though it tends to be less rigorously enforced than at St. Peter’s. Visitors can, however, take photos (no flash) and even, more dubiously, use mobile phones inside (with the exception of the Sistine Chapel). Guided tours are a good way to get the best out of a visit, and are the only way to visit the Vatican Gardens.

Obviously, one trip will not be enough to see everything here. Below are previews of the main highlights, showstoppers, and masterpieces on display (in alphabetical order).

Appartamento Borgia (Borgia Apartments) ★: Created for Pope Alexander VI (the infamous Borgia pope) between 1492 and 1494, these rooms were frescoed with biblical and allegorical scenes by Umbrian painter Pinturicchio and his assistants. The rooms tend to be dimly lit, but look for what is thought to be the earliest European depiction of Native Americans, painted little more than a year after Columbus had returned from the New World.

Musei di Antichità Classiche (Classical Antiquities Museums): The Vatican maintains four classical antiquities museums, the most important being the Museo Pio Clementino ★★★, crammed with Greek and Roman sculptures in the small Belvedere Palace of Innocent VIII. At the heart of the complex lies the Octagonal Court, where highlights include the sculpture of Trojan priest “Laocoön” ★★★ and his two sons locked in a struggle with sea serpents, dating from around 40 b.c., and the exceptional “Belvedere Apollo” ★★★ (a 2nd-c. Roman reproduction of an authentic Greek work from the 4th c. b.c.), the symbol of classic male beauty and a possible inspiration for Michelangelo’s “David.” Look out also for the impressive gilded bronze statue of “Hercules” in the Rotonda, from the late a.d. 2nd century, and the Hall of the Chariot, containing a magnificent sculpture of a chariot combining Roman originals and 18th-century work by Antonio Franzoni.

Museo Gregoriano Egizio ★: Nine rooms packed with plunder from Ancient Egypt, including sarcophagi, mummies, pharaonic statuary, votive bronzes, jewelry, cuneiform tablets from Mesopotamia, inscriptions from Assyrian palaces, and Egyptian hieroglyphics.

Museo Gregoriano Etrusco ★: The core of this collection is a cache of rare Etruscan art treasures dug up in the 19th century, dating from between the 9th and the 1st century b.c. The Romans learned a lot from the Etruscans, as the highly crafted ceramics, bronzes, silver, and gold on display attest. Don’t miss the Regolini-Galassi tomb (7th c. b.c.), unearthed at Cerveteri. The museum is housed within the palazzettos of Innocent VIII (reigned 1484–92) and Pius IV (reigned 1559–65), the latter adorned with frescoes by Federico Barocci and Federico Zuccari.

Pinacoteca (Art Gallery) ★★★: The great painting collections of the popes are displayed within the Pinacoteca, including work from all the big names in Italian art, from Giotto and Fra’ Angelico to Perugino, Raphael, Veronese, and Crespi. Early medieval work occupies Room 1, with the most intriguing piece a keyhole-shaped wood panel of the “Last Judgment” by Nicolò e Giovanni dated to the late 12th century. Giotto takes center stage in Room 2, with the “Stefaneschi Triptych” (six panels) painted for the old St. Peter’s basilica between 1315 and 1320. “Madonna del Magnificat,” Bernardo Daddi’s masterpiece of early Italian Renaissance art, is also here. Fra’ Angelico dominates Room 3, his “Stories of St. Nicholas of Bari” and “Virgin with Child” are justly praised (check out the Virgin’s microscopic eyes in the latter piece). Carlo Crivelli features in Room 6, while decent work by Perugino and Pinturicchio graces Room 7, though most visitors press on to the Raphael salon ★★★ (Room 8), where you can view five paintings by the Renaissance master: The best are the “Coronation of the Virgin,” the “Madonna of Foligno,” and the vast “Transfiguration” (completed shortly before his death). Room 9 boasts Leonardo da Vinci’s “St. Jerome with the Lion” ★★, as well as Giovanni Bellini’s “Pietà.” Room 10 is dedicated to Renaissance Venice, with Titian’s “Madonna of St. Nicholas of the Frari” and Veronese’s “Vision of St. Helen” being paramount. Don’t skip the remaining galleries: Room 11 contains Barocci’s “Annunciation,” while Room 12 is really all about one of the masterpieces of the baroque, Caravaggio’s “Deposition from the Cross” ★★. Crespi is featured in Room 15; Room 17 is full of Bernini sculpture, and the collection ends with an odd ensemble of Russian and Greek Orthodox icons in Room 18.

Stanze di Raffaello (Raphael Rooms) ★★: In the early 16th century, Pope Julius II hired the young Raphael and his workshop to decorate his personal apartments, a series of connecting rooms on the second floor of the Pontifical Palace. Completed between 1508 and 1524, the Raphael Rooms now represent one of the great artistic spectacles inside the Vatican.

The Stanza dell’Incendio served as the Pope’s high court room and later, under Leo X, a dining room, though most of the lavish fresco work here has been attributed to Raphael’s pupils. Leo X himself commissioned much of the artwork here, which explains the themes (past popes with the name Leo). Note the intricate ceiling, painted by Umbrian maestro and Raphael’s first teacher, Perugino.

Raphael is the main focus in the Stanza della Segnatura, originally used as a papal library and private office and home to the awe-inspiring “School of Athens” ★★★ fresco, depicting primarily Greek classical philosophers such as Aristotle, Plato, and Socrates. Many of the figures are thought to be based on portraits of Renaissance artists, including Bramante (on the right as Euclid, drawing on a chalkboard), Leonardo da Vinci (as Plato, the bearded man in the center), and even Raphael himself (in the lower-right corner with a black hat). On the wall opposite stands the equally magnificent “Disputa del Sacramento,” where Raphael used a similar technique; Dante Alighieri stands behind the pontiff on the right, and Fra’ Angelico poses as a monk (which in fact, he was) on the far left.

The Stanza d’Eliodoro was used for the private audiences of the pope and was painted by Raphael immediately after the Segnatura. His aim here was to flatter his papal patron, Julius II: The depiction of the pope driving Attila from Rome was meant to symbolize the contemporary mission of Julius II to drive the French out of Italy. Finally, the Sala di Constantino, used for Papal receptions and official ceremonies, was completed by Raphael’s students after the master’s death but based on his designs and drawings. It’s a jaw-dropping space, commemorating four major episodes in the life of Emperor Constantine.

Sistine Chapel ★★★: Michelangelo labored for 4 years (1508–12) to paint the ceiling of the Sistine Chapel; it is said he spent the entire time on his feet, paint dripping into his eyes. But what a result! The world’ most famous fresco, which, thanks to a massive restoration effort in the 1990s, is as vibrantly colorful and filled with roiling life as it was in 1512. And the chapel is still of central importance to the Catholic Church: The Papal Conclave meets here to elect new popes.

The “Creation of Adam” at the center of the ceiling is one of the best known and most-reproduced images in history, the outstretched hands of God and Adam—not quite touching—an iconic symbol of not just the Renaissance but the age of Enlightenment that followed. Nevertheless, it is somewhat ironic that this is Michelangelo’s best-known work: The artist always regarded himself as a sculptor first and foremost.

The endless waiting in order to get into the chapel inevitably makes the sense of expectation all the greater, but despite the tour groups and the crowds, seeing the frescoes in person is a truly magical experience.

The ceiling frescoes are obviously the main showstoppers, though staring at them tends to take a heavy toll on the neck. Commissioned by Pope Julius II in 1508 and completed in 1512, they primarily depict nine scenes from the Book of Genesis (including the famed “Creation of Adam”), from the “Separation of Light and Darkness” at the altar end to the “Great Flood” and “Drunkenness of Noah.” Surrounding these main frescoes are paintings of twelve people who prophesied the coming of Christ, from Jonah and Isaiah to the Delphic Sibyl. Once you have admired the ceiling, turn your attention to the wall behind the altar. At the age of 60, Michelangelo was summoned to finish the chapel decor 23 years after he finished the ceiling work. Apparently saddened by leaving Florence, and by the poor, morally bankrupt state of Rome at that time, he painted these dark moods in his “Last Judgment,” where he included his own self-portrait on a sagging human hide held by St. Bartholomew (who was martyred by being flayed alive).

Yet the Sistine Chapel isn’t all Michelangelo. The southern wall is covered by a series of astonishing paintings completed in the 1480s: “Moses Leaving to Egypt” by Perugino, the “Trials of Moses” by Botticelli, “The Crossing of the Red Sea” by Cosimo Rosselli (or Domenico Ghirlandaio), “Descent from Mount Sinai” by Cosimo Rosselli (or Piero di Cosimo), Botticelli’s “Punishment of the Rebels,” and Signorelli’s “Testament and Death of Moses.”

On the right-hand, northern wall are Perugino’s “The Baptism of Christ,” Botticelli’s “The Temptations of Christ,” Ghirlandaio’s “Vocation of the Apostles,” Perugino’s “Delivery of the Keys,” and Cosimo Rosselli’s “The Sermon on the Mount” and “Last Supper.” On the eastern wall, originals by Ghirlandaio and Signorelli were painted over by Hendrik van den Broeck’s “The Resurrection” and Matteo da Lecce’s “Disputation over Moses” in the 1570s.

Between April 24 and July 31, and from September 4 to October 30, Vatican Museum visitors will have the extraordinary opportunity to visit the galleries after sunset on Fridays. Twilight visits will allow access to important collections, including the Pio-Clementine Museum, the Egyptian Museum, the Upper Galleries (candelabra, tapestries, and maps), the Raphael Rooms, the Borgia Apartments, the Collection of Modern Religious Art, and the Sistine Chapel, between 7pm to 11pm (last entrance at 9:30pm). Booking online is mandatory.