Christianity has around 2.4 billion followers worldwide — the most followed religion.

The lost city of Ubar is mentioned in Arabian legends.

Particles can exist in multiple states until observed.

Beethoven continued composing after going completely deaf, writing his Ninth Symphony while totally deaf.

The first woman to complete the Boston Marathon officially was Kathrine Switzer in 1967, despite officials trying to pull her off the course.

The first Olympic marathon winner, Spiridon Louis, was a Greek shepherd who had never trained formally.

Eddie 'The Eagle' Edwards became a cultural icon at the 1988 Calgary Olympics despite finishing last in every ski jump event.

The longest recorded point in a professional tennis match lasted over 40 shots.

Particles can exist in multiple states until observed.