deep moat. The surrounding area was swampy and gritty, which complicated the task of the besiegers. The fortifications were provided with arquebuses and machines with a fire range of 2.000 steps. After the siege of Vienna King Matthias urged his troops to encircle Wiener Neustadt, which could pose a possible threat to the conquered lands in later times. He sent captains Stephen Zápolya, Ladislaus Kanizsay, Jakob Székely, Wilhelm Tettauer und Stephan Báthory to begin the siege in 1486. They constructed four siege towers. Upon the prediction of his astrologists he joined them on 13 January 1487 after one year of the siege. After his arrival Matthias realized the errors made by his captains. He found the ring of siege not tight enough. He pulled the circle closer and several watchtowers were built. He instructed the rotation of the reserves in the siege shifts so he was always able to assault with fresh soldiers. The Black Army was ordered to attack the suburbs of Vienna; they crossed the ditch, set fire in the suburbs and drove the inhabitants away, and a part of his troops rushed to assist in the ongoing tense battle at the trenches around the inner city. The drawbridge collapsed, causing many people falling into the trenches where they drowned, others were killed by Hungarians, who advanced to the gates of the city. The next day the citizens withdrew themselves to the Ungarthore in the cover of the drawbridge in the back suburbs of the outer city. Matthias on the other hand reached the moat in front of the Wienerthore () and moved his heavy guns forward, including six enormous ones previously captured from the Ottomans, and brought siege machines that were made to fill the trenches and called for transport pinnaces to serve as mobile bridges. He ordered the constant shooting of the fortifications, and subsequently destroyed six towers including the southwest corner tower. So the garrison of Wiener Neustadt lacked tall buildings to install the long-range firearms, they mounted them to the bell towers of the churches. They were still able to bombard the Hungarian main camp. Despite being a devoted Christian Matthias allowed the shelling of the churches except in case of high risk to conflagrate the town with it. Meanwhile, Johann von Königsberg and Ruprecht von Reichenberg successfully broke through the closures and brought in supplies. Reichenberg even torched two of the siege towers