THE FERRY STOPS at four islands, though most people stay on until Büyükada, which makes for a 90-minute journey. (Only five islands are open to tourism, and two have no residents.) Ferry service didn't begin until the mid-1800s, and before then, the residents here were mainly farmers, fishermen, nuns, and monks. Their scattered small cottages, churches, and Byzantine-era monasteries can be seen throughout the islands.

Kinaliada, named for the reddish color of its soil, is the first stop and the smallest island on the route. A few restaurants line the path along the beach, where a 20-minute stroll will take you from one end of the island to the other. My five-year-old seatmate waves to swimmers in the surf.

As we head back out to sea, new arrivals onboard, the singing and dancing resume. In the midst of the hubbub, Chinese tourists dart between the competing groups, cameras clicking, while agile waiters circulate, balancing coffee, orange juice, pretzels, and tea in tulip-shaped glasses on their trays. Another man hawks visors and hats, protection against the relentless sun. We take photos with people whom we've never met, whose language we don't speak. It's like a party at the UN, but without any translators. The little girl across from me smiles.

Next stop: Burgazada. The harbor is active with small yachts, pleasure boats, restaurants, and shops. Known as the home of the Turkish poet Sait Faik Abasiyanik, this quieter island is preferred to the more commercial Büyükada by many Istanbul residents. Hikers like the vista from the monastery ruins on Hiristo Hill, which are a 40-minute uphill trek away.

I'm tempted to hop off at the third stop on our route when I see the green slopes - twin hills of pine groves - of Heybeliada, which means "Saddlebag Island." The second largest of the islands, Heybeliada is home to the Turkish Naval Academy, founded in 1773, an impressive white edifice adjacent to the ferry dock. In the hills, the theological seminary of the Greek Orthodox Church is set within the Monastery of the Holy Trinity.

The onboard party subsides as the ferry approaches Büyükada. The crowd, most of whom are on a day trip from Istanbul, gather their belongings and disembark. During my island sojourn, whenever I cross paths with my upper-deck mates, we exchange a nod and a smile, like a secret handshake among members of a private club.

THE AREA NEAR the ferry dock at Büyükada is like many seaside tourist resorts in that it has a tangle of streets filled with shops that sell clothes, bathing suits, costume jewelry, film, and postcards, and with fast-food places that offer pizza, ice cream, and local specialty foods. This being Turkey, the local features include izgara köfte (grilled lamb meatballs), iskender kebap (lamb roasted on a vertical spit, piled on flat bread, and topped with tomato and browned butter sauce), and shish kebabs.

A few short blocks from the port, the atmosphere changes from busy commercialism to one of lazy reverie. Part of the islands' mystique is that you have the feeling of stepping back into a quieter era, an illusion aided by the fact that motor vehicles are banned on all the islands. To get around, you must walk, bike, or hire a horse-drawn carriage called a phaeton.

Looking a lot like surreys-with-the-fringe-on-top, phaetons fill the central square and jostle for space on the narrow streets with the skill of seasoned New York cabbies. My vehicle of choice is a bicycle, and I'm told that a person can circumnavigate the island in a few hours. (I manage to see half the island in that time, pedaling lackadaisically and stopping where I please.)

I set off, picnic lunch in basket, but stop barely five minutes later to investigate a handsome white wood structure with twin silver domes and red shuttered windows that open to small balconies facing the sea. In the spacious lobby, which has an elegant carved dark wooden desk, I learn that this is the Splendid Palace Hotel, inaugurated in 1908. In the high-ceilinged dining room, the clink of fine china accompanies several well-dressed elderly women who are lingering over tea, while all is quiet in the parlor, where an elaborate gilded mirror and chandelier hark back to art nouveau roots.

And so it goes as I pedal around the island, stopping every few minutes to take a picture or simply to appreciate Büyükada's quiet beauty. Another aspect of the Princes' Islands' charm is the well-preserved yalis (wooden Ottoman mansions) built in the nineteenth century as summer residences by wealthy Greeks, Armenians, Jews, and members of the Ottoman court. These Victorian-era houses and cottages are different from most architecture in Istanbul. They have elaborate facades, shuttered windows, balconies, decorative columns, and arches, and many have meticulous gardens that in warmer months bloom with raucous honeysuckle, bougainvillea, mimosa, acacia, jasmine, and oleander blossoms.