This is Akkerman fortress, located in the city of Bilhorod-Dnistrovskyi, Odessa region. It was built on the site of the ancient city of Tire by the Genoese, probably in the thirteenth century. Its primary function was to defend the city in the event of an attack from the water, specifically the invasion of the Dnister liman. Architectural researchers associate Ackermann Fortress with Freemasonry through a tetraxis lined with stone cores on the fortress wall. Still, the hypothesis has not been confirmed yet.