Context: The fortified city temporarily fell to the French invasion in 1672 (the Disaster Year); where the French invasion was only stopped west of Utrecht at the Old Hollandic Waterline. In 1674, only two years after the French left, the centre of Utrecht was struck by a tornado. The halt to building before construction of flying buttresses in the 15th century now proved to be the undoing of the central section of the cathedral of St Martin church which collapsed; creating the current Dom square between the tower and choir. In 1713, Utrecht hosted one of the first international peace negotiations when the Treaty of Utrecht settled the War of the Spanish Succession. Since 1723 Utrecht became the centre of the non-Roman Old Catholic Churches in the world.

Question: Who did the fortified city fall to in 1672 
Answer: temporarily fell to the French invasion in 1672 (the Disaster Year); where the French invasion was only stopped west of Utrecht

Question: In 1674 what hit Utrecht 
Answer: the centre of Utrecht was struck by a tornado

Question: What collapsed during the tornado 
Answer: The halt to building before construction of flying buttresses in the 15th century now proved to be the undoing of the central section of the cathedral

Question: What did Utrecht host in 1713 
Answer: In 1713, Utrecht hosted one of the first international peace negotiations when the Treaty of Utrecht settled the War of the Spanish Succession

Question: Since 1723 what has Utrecht become 
Answer: Utrecht became the centre of the non-Roman Old Catholic Churches in the world

Question: Who did the city fall to in the 16th century?
Answer: Unanswerable

Question: Who left the city in 1674?
Answer: Unanswerable

Question: What natural disaister struck in the late 16th century?
Answer: Unanswerable

Question: What did Utrecht host in the 17th century?
Answer: Unanswerable

Question: What did Uterecht become the center of in the 17th century?
Answer: Unanswerable