Tower of London

From Turtledove

The Tower of London is a famous prison in the city of London, England. English monarchs have imprisoned enemies within the Tower for centuries. Queen Elizabeth was imprisoned there twice, first during the reign of her half-sister and predecessor, Mary Tudor, and then after Spain conquered England in 1588. In 1598, a mob of English rebels led by Sir Robert Devereux stormed the Tower and released Elizabeth, then restored her to the throne after expelling the Spanish from England.

Elizabeth herself had imprisoned her cousin, Mary Queen of Scots, in the Tower before executing her in 1587.