The ferry trip to or from the island can be sublime or hellish. On Wednesday (25.7.7) I took the 7.20am from the island to Kadiköy (I'd run out of cash, and had to go to the ATM). It was sublime - that particular ship has an open sun deck on top, so you could enjoy gentle sunshine, a soft breeze, tea + simit, and peace + quiet for 30 minutes.
The 8.50am back could not have been more different. Jam packed with the Istanbul day trippers heading for the beaches for the day. Really grim.
You learn to time your trips to avoid the trippers, but it can't always be done!
- Family Travel
Because you have the asian side , the old town , the european side and also the princes' islands the best thing to do is to use the ferries from side to side.
for tourist they have ferries in 20-30 USD but if you want to feel like a local and go between places cheap the best thing is the local ferries - 1-2 YTL.
You can find ferries in many places : Eminonu , Kadikoy , Uskudar , Beciktas and more.
A ferry to the prince's islands cost us 2 YTL from eminonu.
A ferry to the black sea costs us 7.5 YTL from Besitas.
From Besiktas to Uskudar it cost us 0.75 YTL.
From Eminonu to Kadikoy it cost us 1 YTL.