The Barbican was built at the end of 15th century (1498-1499) and it was the strongest element of the expanded fortifications in Krakow. Barbican was a fortress almost impossible to conquer. Its first test came in 1587 in the battle for the Polish Crown. Krakow's city walls were surrounded by the army of archduke Maksymilian--the royal line of Habsburg. The Attack of his troops was repelled. The pretendant to the throne was forced to leave the city. Another important trial took place during the siege by the Swedish Army-(commonly referred to as "Potop Szwedzki" in polish history) in 1655. Opening hours: summer season (April – October) Monday - Sunday 10.30 am - 6.00 pm closed on every second Monday of the month winter season (November – March) closed There is a one shared ticked for both the Barbican and the Defence Walls. The tickets can be purchased in the branch ticket office on in the Visitor Centre, Sukiennice, Rynek Głowny 1.