Bebek and Arnavutköy are two of the European shore's quietest old villages — wealthy, residential, separated by a kilometre and a half of yalı-lined sahil and connected by the 22 bus. The walk between them is the simplest in Istanbul and one of the most beautiful.
Three kilometres, mostly flat, evening light. Start at Bebek's bay — coffee at Bebek Kahvesi, ten minutes around the parkı, the little white mosque on the water. Then south along the sahil. The first half is yalı-watching: painted wooden Ottoman mansions on the Bosphorus side, money on the hill side, none of it really for visitors. Past Akıntı Burnu the current rips so hard that fishermen don't cast — they hold their lines and the strait pulls fish past them.
Arnavutköy is the dinner. The seafront's meyhanes serve the same çupra, levrek and lüfer they've been serving for a century — pick the one with the locals at it, not the menu in English. The back lanes have the painted wooden houses Arnavutköy is known for; do them on the walk south or after dinner.
End at the Arnavutköy bus stop. The 22 takes you back to Kabataş or onward to Sarıyer.