MADRID—One of Spain’s “ghost airports”—expensive projects that were virtually unused—received just one bid in a bankruptcy auction after costing about €1.1 billion ($1.2 billion) to build. The buyer’s offer: €10,000.

Ciudad Real’s Central airport, about 235 kilometers south of Madrid, became a symbol of the country’s wasteful spending during a construction boom that ended with the financial crisis of 2008, the year the airport opened. The operator of the airport went bankrupt in 2012 after it failed to draw enough traffic.

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