This tower is only called black; on the outside it is built of ordinary stone, and the roof is finished with red tiles. In 1541 a major fire broke out here, after which all the walls were covered with black soot. Since then the tower has been nicknamed 'black'.
It is part of the Romanesque fortification erected on this site as early as the 12th century. Moreover, it was built on the foundation of an even earlier tower, constructed in the 11th century during the reign of Brzhetislav I. Incidentally, in the 14th century this tower was also called golden. The reason is that its roof was covered with gilded tin sheets, which made the building truly sparkle on a sunny day. This served as a kind of indicator of the might of Pražský hrad for those who approached it from the east. But then the fire happened, and the tower became 'black'.
For a long time it housed a prison. The lower floors held criminals convicted of serious crimes, while the upper floors housed debtors. Curiously, the latter had to be fed by their own creditors. Judging by the fact that many died of hunger, the creditors were not particularly concerned about the fate of their wards. In some places, drawings made by the prisoners have even survived on the walls. By the way, the walls here are impressive: at the base they are 3 m thick, and under the roof - 2m.
Finally, an interesting fact: at the beginning of the XX century a secret niche was discovered in the Black Tower, in which 40 Italian carriages had been hidden. Who walled them up there, and for what purpose, is still unknown.
