In ancient times, a low hill on the west side of the Tiber River in Rome overlooked a sports field, or circus, marked by a red granite obelisk from Egypt. In A.D. 64, the Apostle Peter was crucified and buried in its shadow, incising the place in history.

Today people come here to see Michelangelo's “Pieta,” the Raphael rooms, the ancient Laocoon statue or to study some of the crowning architectural achievements of the Italian Renaissance. Some just want to be able to say they've visited the world's smallest country. Others come as religious pilgrims.

sneaked into the magnificent piazza, enfolded by two semicircular colonnades conceived by Gian Lorenzo Bernini in the 17th century. I always feel a shiver when I turn my gaze to St. Peter's Basilica, built between 1506 and 1615 by 18 popes and their favorite architects, including Bramante, Raphael and, of course, Michelangelo, who gave the church its divine dome.

I looked toward the adjacent Vatican Apostolic Palace to see whether the pope might be passing the window of his study on the third floor, where he often appears at noon on Sundays. Pigeons wheeled, and the 140 Christian saints poised in stone on the roofline of the colonnade pointed the way to heaven. Tourists followed guides with open umbrellas or sat on the steps, apparently overwhelmed.

It is overwhelming to contemplate touring the 10-acre basilica, treasury, crypt and dome, and seven miles of galleries in the Vatican Museums. An information bureau, bookstore and post office are tucked into a low building on the south side of the piazza. But it's far better to reserve a place for one of the three excellent tours offered at the Vatican.

n two hours, the Vatican Museums-Sistine Chapel tour skims the surface of the stuff of memories: the Pine Cone Courtyard, with its colossal bronze fountain, a relic of the first St. Peter's Basilica, built beginning about A.D. 326 by Emperor Constantine; the Octagonal Courtyard, which displays classical statuary such as the Greek Laocoon, unearthed in Rome in 1506 and acquired by Pope Julius II at the urging of Michelangelo; the marvelous Gallery of Maps, decorated with 40 historical-topographical maps of Italy devised in the 16th century by papal astronomer Ignazio Danti; the magnificently frescoed Raphael rooms; and, of course, the Sistine Chapel.

Michelangelo's frescoes in the chapel are so big, busy and breathtaking that they seem almost surreal. His St. Peter's dome, on the other hand, has a serene perfection and can best be appreciated on the Vatican gardens tour.

It takes visitors into precincts otherwise accessible only to about 1,000 priests and nuns and 2,500 laypeople who work there.

In the walled compound behind St. Peter's are a bank, printing press, commissary, gas station, railroad, helipad, radio station, tennis court, medical clinic, hotel and offices of L'Osservatore Romano, the Vatican's daily newspaper, as well as a 5,000-pound fragment of the Berlin Wall and a full-scale reproduction of the grotto of Lourdes.

The third tour at the Vatican is my favorite. It visits the pre-Christian necropolis underneath St. Peter's Basilica, where excavation began in the 1940s after Roman artifacts were discovered during the burial of Pope Pius XI.

I went on an excavations tour led by a priest from Detroit who devotes his vacations to conducting the subterranean exploration. From an entrance on the south side of the sanctuary, the group descended on a network of narrow, winding stairs to the basement of St. Peter's, where we saw intact Roman mausoleums – decorated with frescoes, mosaics and statuary – formerly sealed beneath rubble from the first basilica.

It was to this pagan necropolis that St. Peter's body was taken after his crucifixion, many scholars believe.

We stopped precisely under the high altar where both tradition and ancient graffiti suggest that St. Peter was laid to rest, although proof is lacking and no further excavation is under way. But for many people, just being in this remarkable place is believing.

For me, no proof is needed. Regardless of where he was buried, St. Peter is the rock on which the Vatican was built, spiritual home to a billion Roman Catholics.

Monaco is a silver slipper of a country on a little shelf of the French Riviera not much bigger than Monte Carlo, its capital.

I decided to do it in style in the spring with Sarah, my 20-year-old niece. During the Grand Prix, I booked a room for one night at the luxurious Hotel Port Palace overlooking the harbor and got tickets to watch a day of practice runs from the grandstand.

On the drive from Marseille, France, we stopped to have our rented Volvo station wagon washed and polished just to make a good impression in the car-crazy principality, home of Formula One's most glamorous race since 1929.

We had our choice of the low, middle or high corniche, as the roads that ply the 20-mile strip of Mediterranean coast between Nice, France, and the Italian border are known. Even the low one, which we chose, can be hair-raising.

Once we crossed the border into Monaco, we hit traffic, diversions and barricades. During the Grand Prix (which takes place about the same time as the nearby Cannes Film Festival) the streets of waterfront Monte Carlo are turned into a tight, 2-mile track with a tunnel and 19 treacherous hairpin curves. F1 champion Nelson Piquet once said that driving the course is like riding a bike in a living room.

Sarah and I don't know a pole position (the top starting spot in an F1 event) from a chicane (an S-curve on a course), but we were willing to learn while indulging ourselves at the Port Palace. The hotel occupies a stylish high-rise decorated with vintage photos of such movie stars as Jean-Paul Belmondo and Clint Eastwood.

Cinched in by the Grand Prix course on two sides, its front door is at harbor level and its rooftop terrace is on Avenue d'Ostende, which yields directly to Monte Carlo's fabled Belle Epoque-style casino.

Our double room overlooked the harbor, at the moment full of yachts with front-row views of the track from their polished decks. The rate for the night was $400, in line with premium prices during the five-day Grand Prix, when businesses in the principality pull in as much as they make during five months of low season.

That night, Sarah and I put on frocks and high-heeled sandals to visit the casino, surrounded by fountains and flower gardens.

Outside, a Bentley was pulling up at the fabled Hotel de Paris, built in 1864. But when we tried to enter, the doorman turned us back, pointing to our apparently inappropriate footwear. So we adjourned to the equally sumptuous Hotel Metropole nearby for cocktails, which cost twice as much as the pizza we had for dinner later.

The next morning we made our way to the business district along Rue Grimaldi, where the Automobile Club of Monaco, which sponsors the event, had a boutique selling Grand Prix T-shirts, watches and earplugs. A booth nearby was renting hand-held TV monitors so sports fans could follow the progress on the track wherever they went.

We watched for a while from our grandstand seats in front of the harbor, then climbed to the upper town atop the rock where a fortress has stood since the 13th century. In 1297 Francois Grimaldi, an exiled nobleman from Genoa, entered the fort disguised as a monk, thereby gaining temporary control of the stronghold. The Grimaldis ultimately became the sovereign lords of Monaco, thanks to treaties forged with France.

Their palace at the summit of the rock is open to visitors. So Sarah and I took the tour, with audio guides narrated by Prince Albert II. We admired the red and gold chamber where the English Duke of York died while visiting the principality on a sailing vacation in 1767 and the many portraits of beautiful Princess Grace, whose death in a 1982 car accident stunned the world.

Then Sarah and I had to hit the road because 24 hours at the Monaco Grand Prix was all we could afford.

San Marino, set on an outcropping of the Apennine Mountains, is the world's oldest republic, based on its founding in the early part of the 4th century during the reign of Roman Emperor Diocletian, when an escaped Christian slave named Marinus (“Marino” in Italian) found refuge on this peak. The tiny settlement he founded wasn't worth Rome's wrath, to the relief of Marino. He was later canonized.

The commune managed to remain free by good fortune, canny alliances and pluck. Its independence was confirmed by several popes and, after finding refuge there in the wars leading up to the 1870 union of the Italian peninsula, republican leader Giuseppe Garibaldi did not insist on incorporating San Marino into the modern state of Italy that now surrounds it.

San Marino's motto, “Libertas,” appears on its crest, along with the three towers built in the Middle Ages atop Mount Titano.

The iconic bastions reared up boldly as I followed a switchbacking road to the old town and capital of San Marino, a car-free zone built on a series of terraces. Near the main gate a policeman gave me a map showing about a dozen parking lots tucked around the hill town. I found a spot close to the top, then carried my bag to the nearby Hotel Rosa, underneath the first tower, known as La Rocca.

Like everything in Italian-speaking San Marino, the hotel and its terrace restaurant exude good government. My modern single on the second floor lacked charm, but it had a window with a pleasing view over the roofs of the old town. Moreover, the Hotel Rosa is just a few doors away from the Waxworks Museum.

San Marino also has Curiosity, Torture and Modern Weaponry museums, legions of bus tourists and a virtual plague of souvenir shops, where you'll find items as diverse as designer watches and Native American headdresses. Most interesting are the stores devoted to imitation weapons, with medieval maces alongside AK-47s. A shopkeeper explained that the weapons are purchased mostly by historical re-enactors.

A quick stroll that afternoon told me that the town caters wholeheartedly to visitors, later confirmed when I read in a brochure that half the republic's revenue comes from tourism. But I can cope with tourist traps, so I unpacked and had dinner at the Hotel Rosa.

San Marino cuisine resembles that of nearby Italian regions, including Emilia-Romagna, with plentiful seafood from the nearby Adriatic. I had a delicious fried calamari starter, followed by baby clam spaghetti in red sauce. The meal was accompanied by a half carafe of highly palatable red wine from one of San Marino's 13 commercial vintners.

The next morning I began exploring the old town by having my picture taken with a guard in a white-feathered shako at the Palazzo Pubblico on the Piazza della Liberta. The boxy, faux medieval building, surmounted by a clock tower, is the seat of San Marino's singular government, overseen by two captains-regent who stand for re-election every six months.

The 19th-century San Marino Basilica above the Piazza della Liberta enshrines the founding saint's bones. Below is the post office, which sells prized San Marino stamps and coins, and the State Museum. It has a collection of forgettable Italian Baroque paintings and a far more interesting display of pendants, earrings, hairpins and necklaces from the Treasure of Domagnano, found nearby in the tomb of a 6th-century noblewoman. Alas, most of the items are reproductions of originals now at museums in Berlin, London and New York.

I saw a medieval crossbow demonstration, took the inclined railroad down to the hamlet of Borgo Maggiore, then walked a path along the ridgeline of Mount Titano, passing all three towers. It's said that from here you can sometimes see right across the Adriatic to the coast of Croatia. But all I could spy was the territory of San Marino spread over the surrounding hills and valleys.

The next morning, having visited all the major sites, I couldn't figure out how to spend my last day in San Marino. But then I remembered the view from Mount Titano and set out in the car to sample the pleasures of the countryside.

The capital is surrounded by eight little townships, known as “castellos” for their ancient hilltop castles, where most of the country's 30,000 residents live. It took 10 minutes to reach pretty Fiorentino, where I stopped at a supermarket and bought a sandwich.

I planned to picnic in neighboring Montegiordano. But when I got there, an innkeeper told me to go to Albereto di Montescudo, an even smaller hill town reached by a precariously winding one-lane road. Somewhere along the way I must have crossed the border because Albereto is in Italy.

In the Middle Ages, the diminutive castello was controlled by the fearsome Malatesta family. Now it's an elegant restaurant with a terrace overlooking Mount Titano.

While my sandwich spoiled in the car, I had lunch, starting with a plate of divine pistachio and artichoke ravioli. A fillet of white fish in puttanesca sauce came next, and dessert was cinnamon gelato with an espresso.

All the while, I gazed across the valley at the triple towers, wondering why we need big countries anyway, when there are beautiful, free and idiosyncratic small ones like San Marino.