The Graft Bastion was built between 1515 and 1521 to ensure the communication of the defenders of the White Tower with the fortress. For this purpose it had a movable gate. Of rectangular shape, based on a thickness of about 4 meters, the fortification is provided with shooting holes with wooden clasps and casting holes. Its position, located almost in the middle of the northwest side of the fortress, made the bastion acquire another importance. From him were protected the path that passes near the stream of the same name, as well as the outer walls of that part. For this, the bastion had firing holes and fuel tanks that have been preserved to this day. It was defended and maintained by the guild of the saddlers (the masters of saddles, harnesses, belts). Due to a torrential rain that occurred on August 24, 1809, the walls of the fortress weakened in the Graft area and a consolidation was needed. In 1822 three support arches were built over the stream, of which one still exists today.
Renovated in 2004 – 2005, inside the bastion a museum point and a craft store were set up. Also, the route to the White Tower was redone, through a series of steep steps that go up the slope of the Warthe hill.