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Nicolas Janberg's Structurae: Eiffel Tower
Information on the Eiffel Tower can be found here at Nicolas Janberg's Structurae, including a chronology of its history, technical specifications, construction details, and information about the tower's architect, builder, and dimensions.
Wikimedia
Wikipedia: Eiffel Tower
The article from Wikipedia on the Eiffel Tower discusses the history of the monument and its construction. It also describes the tower's famous ironwork and tells of its significance to the city of Paris.