The European Bosphorus runs out of villages eventually, and Emirgan and Sarıyer are the last two big ones before the strait opens to the Black Sea. The walk between them is sahil all the way, with a tulip park, a museum of Ottoman calligraphy, and the city's most serious fish market at the end.
Five kilometres, mostly flat, lunch is part of the walk. The 25E bus from Kabataş drops you at Emirgan. Start in the park — the tulip festival every April makes it the visual signature of Istanbul in spring; the rest of the year it's parkland with three Ottoman kiosks and the Bosphorus below.
The Sakıp Sabancı Müzesi is up the road in the family's old yalı. The Ottoman calligraphy collection is the permanent show — illuminated Korans, sultanic decrees, the floral tuğra the sultans signed with. The terrace restaurant overlooks the strait. Push north along the sahil — about ninety minutes — through İstinye and Yeniköy and Tarabya to Sarıyer's fish market. Lunch on what you watched come off the ice. The ferry back to Eminönü is forty-five unhurried minutes along the upper Bosphorus.

