Eye

When you start discussing eye-watering automotive prices most people have to think of the Bugatti Veyron and this list is no exception.

A recent addition to professional tennis has been the adoption of electronic review technology coupled with a point-challenge system, which allows a player to contest the line call of a point, a system known as Hawk-Eye.

Jump forward eleven years later, and an eye-watering four hundred guests now make a booking every two minutes.

The Great Wall of China cannot be seen from space by the human eye without aid.

Mars is often referred to as the "Red Planet" because the reddish iron oxide prevalent on its surface gives it a reddish appearance that is distinctive among the astronomical bodies visible to the naked eye.

It is, according to drone schools, illegal to fly your drone that's capable of traveling up to a mile or more any further than you can see it with the naked eye or above 400 feet.

Jupiter can be seen with the naked eye.

You can ride on a big Ferris wheel called the London Eye.