Most İstanbullus refer to the Princes' Islands as 'The Islands' (Adalar), as they are the only islands around the city. They lie about 20km southeast of the city in the Sea of Marmara, and make a great destination for a day escape from the city.
You'll realise after landing that there are no cars on the islands, something that comes as a welcome relief after the traffic mayhem of the city. Except for the necessary police, fire and sanitation vehicles, transportation is by bicycle, horse-drawn carriage and foot, as in centuries past.
All of the islands are busy in summer, particularly on weekends. For that reason, avoid a Sunday visit. If you wish to stay overnight during the summer months, book ahead. Many hotels are closed during winter.
There are nine islands in the Princes' Islands group and the ferry stops at four of these. Year-round there are 15,000 permanent residents scattered across the six islands that are populated, but numbers swell to 100,000 or so during summer when İstanbullus - many of whom have holiday homes on the islands - escape the city heat. The small islands of Kınalıada and Burgazada are the ferry's first stops; frankly, neither offers much reward for the trouble of getting off the ferry.
In contrast, the charming island of Heybeliada (Heybeli for short) has much to offer the visitor. It's home to the Deniz Lisesi (Turkish Navel Academy), which was founded in 1773, and which you'll see to the left of the ferry dock as you arrive, and it has a number of restaurants and a thriving shopping strip with bakeries and delicatessens selling picnic provisions to day-trippers, who come here on weekends to walk in the pine groves and swim from the tiny (but crowded) beaches. The island's major landmark is the hilltop Hagia Triada Monastery (%351 8563). Perched above a picturesque line of poplar trees in a spot that has been occupied by a Greek monastery since Byzantine times, this building dates from 1894. It functioned as a Greek Orthodox theological school until 1971, when it was closed on the government's orders, and has an internationally renowned library. There are signs that it may re-open soon. You may be able to visit if you call ahead.
The largest island in the group, Büyükada (Great Island) shows is impressive from the ferry, with gingerbread villas climbing up the slopes of the hill and the bulbous twin cupolas of the Splendid Otel providing an unmistakable landmark. It's a truly lovely spot to spend an afternoon.
The ferry terminal is an attractive building in the Ottoman kiosk style; it dates from 1899. Inside there's a pleasant tile-decorated café with an outdoor terrace, as well as a Tourist Information Office. Eateries serve fresh fish to the left of the ferry terminal, next to an ATM.
The island's main drawcard is the Greek Monastery of St George, in the 'saddle' between Büyükada's two highest hills. To get there, walk from the ferry straight ahead to the clock tower in İskele Square (Dock Square). The shopping district is left along Recep Koç Sokak. Bear right onto 23 Nisan Caddesi, then head along Çankaya Caddesi up the hill to the monastery; when you come to a fork in the road veer right. The walk (at least one hour) takes you past a long progression of impressive wooden villas set in gardens. About a quarter of the way up on the left is the Büyükada Kültür Evi, a charming spot where you can enjoy a tea or coffee in a garden setting. The house itself dates from 1878 and was restored in 1998. After 40 minutes or so you will reach a reserve called 'Luna Park' by the locals. The monastery is a 25-minute walk up an extremely steep hill from here. Some visitors hire a donkey to take them up the hill and back for around YTL10. As you ascend, you'll see countless pieces of cloth tied to the branches of trees along the path - each represents a prayer, most made by female supplicants visiting the monastery to pray for a child.
Bicycles are available for rent in several of the town's shops, and shops on the market street can provide picnic supplies, though food is cheaper on the mainland. Just off the clock tower square and opposite the Splendid Otel there are fayton stands. Hire one for a long tour of the town, hills and shore (one hour around YTL45) or a shorter tour of the town (around YTL35). It costs around YTL16 to be taken to Luna Park. A shop just near the fayton stand hires out bicycles (per hour around YTL3-3).
Fourteen ferries run to the islands each day from 06:50 to midnight, departing from Kabataş' 'Adalar İskelesi' dock. The most useful departure times for day-trippers are 09:30, 10:00 and 11:30. On summer weekends, board the vessel and grab a seat at least half an hour before departure time unless you want to stand the whole way. The trip costs around YTL3 the islands and the same for each leg between the islands and the return trip. The cheapest and easiest way to pay is to use your Akbil. To be safe, check the timetable at www.ido.com.tr, as the schedule can change.The ferry steams away from Kabataş and on its journey treats passengers to fine views of Topkapı Palace, Aya Sofya and the Blue Mosque on the right, and Üsküdar and Haydarpaşa on the left. After 20 minutes the ferry makes a quick stop at Kadıköy on the Asian side before making its way to the first island, Kınalıada. This leg takes 30 minutes. After this, it's another 15 minutes to Burgazada; another 15 minutes again to Heybeliada, the second-largest island; and another 10 minutes to Büyükada, the largest island in the group.Ferries return to İstanbul every 1.5 hours or so. The last ferry of the day leaves Büyükada at 22:00 and Heybeliada at 22:15.