[watchin]

And from here: 

 

The site of La Mezquita originally bore a church. Then, after the Moors conquered Cordoba in the 8th century, they demolished the church and built the Mezquita (mosque). 

[ArrogantBustard]

Thanks for the links. Here's one about Hagia Sophia. Thank the Greek Orthodox for this wonderful website. The Turks have turned it into a museum, and are doing a pretty good job of preserving all it's history, both Christian and mohammedan.