Madrid, Spain - Sitting 2,000 metres above sea level on the southern edge of the province of Teruel, the Javalambre astrological observation station is said to offer one of the clearest night skies in Europe for stargazers.

But cast your eyes back down to earth, and there is a grim reason for Javalambre's much-appreciated dearth of light pollution.

For decades now, Teruel's population has been draining away, and in 2017 some parts had sunk to an average of 1.63 inhabitants per square kilometre - lower than that of Lapland in Sweden, internationally famous for being one of Europe's most remote regions.

And it is not just Teruel. Spain's rural depopulation crisis has reached a point where five of its regions - Aragon, Castilla y Leon, Castilla-La Mancha, Extremadura and La Riojamake up 53 percent of its territory, but now have only 15 percent of its residents.

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In the past 50 years, Spain's rural regions have lost 28 percent of their population, and are now popularly known as la Espana vacia - empty Spain. In Teruel, part of Aragon, with a drop in population of nine percent in the past decade alone, the loss has been particularly noticeable.

"It's a real environmental, human and historic problem - a disaster for the whole country," Tomas Guitarte tells Al Jazeera.

In November's elections, Guitarte became the first MP to represent a Spanish political association specifically created to fight rural depopulation. It is named Teruel Existe ["Teruel Exists"].

Although the industrial development plans forged by Spain's former dictator, General Francisco Franco, kickstarted the rural depopulation process