Located in the Gebze district of Kocaeli, Eskihisar Castle holds great importance in terms of the region's historical and cultural heritage. Having hosted many civilizations, this castle bears traces from various periods, from the Byzantine Empire to the Ottoman Empire, and is notable for its strategic location.
Today, it has transcended its status as merely a historical structure, becoming a symbol that enhances the region's tourism value. Eskihisar Castle is an important cultural heritage site that should be visited by both domestic and foreign tourists.
Sunset in Eskihisar (Photo: Ahsen Güneş)
Geographic Location and Historical Background
Eskihisar Castle is built on a hill approximately 50 meters above sea level in Eskihisar Village, Gebze district of Kocaeli. Its height and strategic surrounding location, overlooking the Sea of Marmara, indicate its purpose as a defensive structure for the region. The historical importance of Eskihisar Castle stems not only from its military defensive role. Its location at the intersection of the region's trade and transportation routes also increased its strategic value, both militarily and economically.
Byzantine Period and the Construction of the Castle
While precise information on the construction date of Eskihisar Castle is lacking, it is believed to have been first built during the Byzantine period. The Byzantines constructed many castles along the coast, particularly to control the Sea of Marmara. Eskihisar Castle served as an important defensive stronghold against attacks from the sea during this period. During the weakening of the Byzantine Empire, the castle fell into the hands of other civilizations from time to time, but it always maintained its military and strategic importance.
Ottoman Period and the Reuse of the Castle
Eskihisar Castle was also used as an important military base during the Ottoman Empire. Structural renovations were undertaken to ensure security against threats from the sea, and more modern defense systems were integrated. Towards the end of the Ottoman period, the castle was not only used for military purposes but also functioned as an observation tower overseeing the region's trade.
Structural Features and Architecture
Eskihisar Castle has been developed with various additions by different civilizations over time, but generally retains architectural elements from the Byzantine and Ottoman periods. The castle is surrounded by walls. The towers and turrets located on the walls clearly show that the structure was built for defensive purposes.
Outer Walls and Defense Systems
The most striking feature of the castle is its extensive defensive walls. These walls served a defensive purpose against attacks from land and sea. The wall stones are quite sturdy in terms of stonework and have been repaired many times over time. Furthermore, the turrets on the walls allowed for the detection of approaching enemies from long distances, thus serving as an early warning system.

Eskihisar Castle (Gebze Governorship)
Towers and Interior Spaces
Inside Eskihisar Castle, there are structures consisting of several rooms. These structures served as the center of the castle's administration and military activities. The interiors are quite simple, but functionally designed in line with the castle's defensive purpose. The towers are one of the elements that increase the castle's defense capacity, and their height allowed for the surveillance of all movement on the sea route.

A Detail from the Tower (Kocaeli Metropolitan Municipality)
Changes Over Time
The additions and restorations made to the castle are among the important elements that bear the traces of past civilizations. These changes affected the castle's military function and aesthetic structure, shaping its appearance over time according to the needs of the period. Additions made, especially during the Ottoman period, ensured that the structure acquired a more modern defense structure.
Tourism and Cultural Heritage
Today, Eskihisar Castle is used as a historical structure and a tourist destination. Visitors, during their visits to the castle, both acquire historical information and benefit from various social facilities offered in the region. Guided tours specific to the castle tell visitors about the historical process of the castle, its purpose of construction, and the effects of this process on life in the region.
Restoration Works and Preservation
Local governments and relevant institutions have undertaken various restoration works for the preservation of Eskihisar Castle. These studies aimed to preserve the castle's historical texture, ensure its structural integrity, and convey its traditional architectural elements to the present day. At the same time, landscaping arrangements and infrastructure improvements around the castle have enhanced the visitor experience.
Visitor Opportunities and Events
The castle also hosts various social events to increase the region's tourism potential. Cultural events, festivals, exhibitions, and concerts held at Eskihisar Castle increase the participation of the local population and play an important role in promoting the region's cultural values. These events contribute to the castle being more than just a historical site, but a cultural meeting point.



