Urban explorer and photographer Thomas Windisch of Graz, Austria traveled 12,000 miles across Europe to capture images of luxurious hotels that once hosted royals and the world's elite, but are now crumbling in decay.

While some of the more than 100 hotels Windisch photographed look as though they could still be hosting grand events in their ballrooms, others are more obviously dilapidated, with dirty mattresses, dusty, broken furniture and moss-covered floors. Many of the resorts haven't been used in several decades.

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"It's pretty awesome to see areas of a hotel that are normally not accessible for guests and to understand how a big hotel works in the background," . "And of course, the decay and reclaiming of these buildings by nature add a bit of a surreal and mystic touch, which makes them unique and even more interesting."

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