The Church of the Sycorax, also known as the Convent of Saint Sabbas, was a copy of Westminster Abbey located on Shadow Cay. It was created by the Sycorax using magma-sculpting technology, as a shrine to where Fadros Pallujikaa fell to his death in 2006 after the Tenth Doctor defeated him.
The Sycorax hypnotised humanity into believing the building was constructed in 1823. In 2009, the church was destroyed when the Doctor overloaded the magma-sculptor by having it scan and recreate the whole of Earth on Shadow Cay. (COMIC: The Widow's Curse)