(CNN) Imagine if tennis legends Roger Federer and Serena Williams lived and trained in the same small town. Both arguably the greatest of all time in their own disciple, living and training side by side, pushing each other to new heights.

Or perhaps soccer stars Cristiano Ronaldo, Lionel Messi and Neymar all taking root in the same small village in Spain. Bumping into each other at the grocery store and all getting together for dinner once a week.

You can't. It just wouldn't happen.

Well, in the sport of competitive CrossFit, that unlikely scenario has become reality with arguably the three greatest competitors in the sport's history all residing within a few short miles of each other, deep in the heart of rural Tennessee.

As a result, Cookeville, a city of just 30,000 people, has become a mecca in CrossFit, with devotees making pilgrimages all over the world just to work out in the company of some of the fittest people on Earth.

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