Princes' Islands

The Princes’ Islands are about 20km south of Istanbul and take about an hour by ferry.  They are pedestrian only so you don’t get loud traffic noise like back in the city.  The largest island is the most developed and has the most cafés and restaurants.  This is the one I stopped at.

Most people go on a day trip like I did, but if you want, there are a few accommodation options.
This is a pension, or guesthouse.  Would you stay here?  It looks like some sort of set for a horror film!  There were people staying here, you could see them sitting in the lobby.  In case you did want to stay in this area, there was a little town that seemed to have some more upmarket options.
There is good hiking here as the island has two peaks.  On the top of one is a church.  The church itself is quite small, but the view from the back of it is quite spectacular.
You can see the stretching out Istanbul in the background.  The Asian side is straight ahead and the European side on the far left, mostly off camera.  Here is another view from the ferry dock.
On the other peak you can see what was an orphanage.  Apparently it’s the second largest wooden building in the world.  It’s now deteriorating pretty badly so you cannot go in, only up to the gate.
There are a lot of cafés all over the island.  I noticed if you went off the beaten path a bit, the prices for coffee seemed to drop pretty quickly.  You certainly didn’t need to worry about carrying enough water, people were selling it all over the place.
If you do go to the islands, make sure to note the time of the last ferry.  Apparently people have been unexpectedly stuck here for the night!  Also, I’m told they ferries get very busy on weekends and holidays.