Eskihisar is a small coastal town in Eastern Marmara. It’s located just east of easternmost suburbs of Istanbul and on the northern shore of the Gulf of Izmit.
From Istanbul, take D100 highway to east. Follow “Eskihisar” signs once you left the suburbs of Istanbul behind and crossed the provincial boundary of Kocaeli. It normally takes about an hour from central parts of Istanbul — unless the highway is congested as is usual.
Frequent suburban trains (banliyö treni; 1.50 TL pp) depart from Haydarpaşa station in Istanbul's Asian Side to Gebze, making the route in roughly an hour. From Gebze station, Eskihisar is about 30 minutes away on foot. Minibuses may also be available.
- Eskihisar Citadel (Eskihisar Kalesi).
- Osman Hamdi Bey Museum (Osman Hamdi Bey Müzesi), (on the waterfront street; very near the ferry harbour). A renovated white wooden Victorian mansion that wouldn't be out of place in Büyükada. Formerly owned by Osman Hamdi Bey, founder of the Istanbul Archaeology Museum.
There are some restaurants on the shore to the left of the ferry jetty.
There are some hotels/guesthouses (pansiyon) in the streets to the left of the ferry jetty.
- The only reason for you to be in this town is probably to take the ferries  to Topçular near Yalova across the Gulf of Izmit. Ferries are quite frequent and take about 40-45 minutes to reach the other side. While passengers without a vehicle pay 2.80 TL/person, flat fare for cars is 45 TL one-way, i.e. it is not dependent on how many people are riding in the car. Larger vehicles pay substantially more.