But some are clearer than others - do you know what an empty red sign means? Circular road signs give orders. Red circles give an instruction that you must follow, such as speed limits.

Inside this red circle lies the world’s driest non-polar desert, a place where rain is so scarce it may not fall for years or ...

Within this red circle lies one of the most extreme environments on our planet—the driest non-polar desert in the world.

What does an empty red road sign mean? Circular road signs give orders. Red circles give an instruction that you must follow, such as speed limits. The blank sign with a red border means that all ...