Today, the Zagreb Cathedral is dedicated to the Assumption of the Blessed Virgin Mary. It is 77 meters long and 46.20 meters wide. The north tower is 105 meters in height, while the south tower is 104 meters. The internal area is 1617 m2 and up to 5000 people can attend mass in the Cathedral.
The Zagreb Diocese was founded by the Hungarian King Ladislaus in about 1093/4, when he ordered that a cathedral be built. The construction likely began after 1102 and was dedicated in 1217. It was built in the Romanesque transitional style. The new cathedral was heavily damaged in the 1242 attack by the Tartars, and was renovated in 1264 and 1284 by Bishop Timothy in the Gothic style. At that time, the eastern, basilica section of the cathedral was built. The western, manor section, with equally high vaults in all three naves was built throughout the 14 and 15th centuries and into the 16th century. From the second half of the 15th century to the first half of the 16th century, the fortress walls and towers were built around the Cathedral to defend against the Turks. In the 17th century, the Cathedral was damaged in two large fires.
The restoration lasted until the second half of the 17th century. As part of the final works, the massive bell tower was built on the south side, and also served as a watchtower. At the end of the 17th and 18th centuries, the Cathedral received marble elements: the pulpit in 1698 and the remaining 32 altars – very valuable examples of the Baroque style. In the 19th century, during the period of Bishop Juraj Haulika, the sanctuary (presbytery) was renovated: a new neo-Gothic wooden altar was added from the sculptor Sickinger from Munich. The organ builder Walcker from Ludwigsburg created the new organ, which today is still found in the Cathedral. It is considered to be among the ten most significant in the world.
In 1880, Zagreb was heavily hit by a serious earthquake and the Cathedral was also damaged. The restoration plans were drafted by Vienna architect Fridrich Schmidt, and the restoration was conducted by the architect Hermann Bolle.
The remains of the Croatian noblemen Petar Zrinski and Fran Krsto Frankopan, killed at Wiener Neustadt on 30 April, 1671, are buried in the Cathedral.