UPDATE MARCH 2022: Linking of HES Code with Istanbul Card is no longer required when using public transportation.
Following the mandatory use of HES code, Istanbul Metropolitan Municipality took the necessary steps for the new period of linking HES codes with Istanbulkart. After January 15th, Istanbulkarts without a linked HES code cannot be used on public transportation. Card users can enter their personal information together with their HES Code at the website provided at this post. Linking the HES code to the card can be done easily by entering the required fields on the website.
Princes’ Islands are located in the Sea of Marmara. The name comes from the exiled princes of Byzantine era. Consisting of 9 islands in total, the archipelago is popular both among tourists and locals who want to escape the hustle of the city. Four of the islands are open to public; Büyükada, Heybeliada, Kınalıada and Burgazada. You can take the ferries from Kabataş. It takes about an hour to get to the islands but the ferry ride is quite enjoyable itself.
Princes’ Islands Location:
Istanbul Ferry Lines (Big Ferries) – Ticket Price is 22 TL one way.