The White Tower is a central tower, the old keep, at the Tower of London. It was started in 1078 by William the Conqueror who ordered the White Tower to be built inside the south-east angle of The City walls, adjacent to the River Thames. This was as much to protect the Normans from the people of the City of London as to protect London from outside invaders. William ordered the Tower to be built of Caen stone, which he had specially imported from France, and appointed Gundulf, Bishop of Rochester as the architect. The tower was finished around 1087 by his sons and successors, William Rufus and Henry I.
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