These buildings cost billions but are abandoned today
Maginot Line, France, cost: $3.7 billion (£3bn)
Built during the 1930s, the Maginot Line cost a staggering 3 billion francs to build, the equivalent of $3.7 billion (£3bn) today. The line, named after war minister Andre Maginot, consisted of obstacles, fortifications and weapons stretching along France’s borders with Italy, Switzerland, Germany and Luxembourg. It was designed to prevent German troops invading during World War II.
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