The gothic style krakow barbican is a fortified external castle that used to be linked with the main Florian's gate and city walls in medieval times.
This partly round outbuilding was important part of Krakow fortification as the invaders needed to enter this tricky building to get acces to the city.
It was developed as a feature strengthening the main entrance by directing the enemy through the narrow passages - which made the invaders an easy target for the defeners. It was also called a death trap.
The building was built in 1498 and is one of three such fortified outposts still surviving in Europe.
The edifice has a cylindrical brick structurewith surrounding moat with inner courtyard and seven turrets(small towers) with pointed roofs.
Its masonary brick wall are 3m thick and hold 130 embrasures(openings in crenelations - an arrow slit/loophole/arrow loop)
Krakow barbican is concidered to be the masterpiece of medieval military engineering