First built in 9th Century, San Zaccaria is dedicated to the father of St. John the Baptist, Zechariah, who is supposedly buried there. Other locations in which St. Zechariah is supposedly buried: the Gandzasar Monastery in Nagorno Karabakh, Yad Avshalom, the Great Mosque of Aleppo and the Valley of Jehoshaphat.
San Zaccaria burned down in 1105, killing more than a 100 nuns. The church was rebuilt around 1170 and then later redone with a mixture of Gothic and Renaissance styles.
Ironically, in the Renaissance, it flourished as the nunnery of choice for the daughters of the noblest families in Venice, who obviously didn’t know the building’s story.