The unifinished interior at the AVE (High Speed Train) station in Yebes, Guadalajara. It was initially built for the inhabitants of Valdeluz residential city, which is vastly underpopulated. Due to favourable interest rates and readily available mortgages, Spain experienced a construction boom in the years leading up to 2008. The financial crisis of 2008 caused the real estate bubble to burst leaving millions of homes and other buildings vacant. .