The games of cat and mouse urban explorers play with the buildings security guards - and lengths they're willing go to in an effort to outwit them.
They climb the world's tallest skyscrapers and their vertigo inducing videos are watched by millions online. But there is one question on everybody's lips - why aren't these people scared?
Although urban explorers come from all walks of life and all backgrounds, most are united by a certain disregard for authority. Unrestricted looks at the influence counter culture plays in urbex.
While urban exploration may be watched and admired by millions online, it is not without its detractors. Many explorers receive fierce criticism from the press and public.
Explorations now take place in every country and almost every city on earth, but there are a select few sites that are so risky to conquer that only the most daring urban explorers will even attempt them.
With millions of people heading out and exploring their local city's and millions more watching online, this has been called the golden age of urbex. But its future is uncertain.
Not all urban exploration is about going to the tallest buildings. Many people first get into urbex because of a fundamental desire to seek out the hidden side of their city.
As urban exploration has been drawn ever more into the public spotlight, there has been a growing pressure for each video to be more amazing, more jaw dropping than the last.