Secret passages, also commonly referred to as hidden passages or secret tunnels, are hidden routes used for stealthy travel, escape, or movement of people and goods. Such passageways are sometimes inside buildings leading to secret rooms. Others allow occupants to enter or exit buildings without being seen. Hidden passages and secret rooms have been built in castles and houses owned by heads of state, the wealthy, criminals, and abolitionists associated with the American Underground Railroad. These passages have helped besieged rulers to escape from their attackers, including Pope Alexander VI in 1494, Pope Clement VII in 1527 and Marie Antoinette in 1789. Passages and tunnels have been used by criminals, armies and political organizations to smuggle goods and people or conceal their activities.
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