How Great is Great Britain?

How long is the coastline of Great Britain? Go on. Have a guess.It sounds like the sort of question that should have a straightforward answer. Surely someone, at some point, has walked around Britain with a very long tape measure and worked it out.Unfortunately, the coastline has other ideas.The problem is that Britain's coast is full of bays, headlands, inlets and innumerable little squiggly bits. Measure it using a fairly large ruler and you'll skip over much of that detail. Use a smaller ruler and suddenly you're measuring around all those extra twists and turns - and Britain's coastline mysteriously gets longer.This is the Coastline Paradox: the awkward fact that there isn't really one definitive answer to the question How long is the coastline of Great Britain?In 1967, mathematician Benoit Mandelbrot famously explored exactly this problem in his paper How Long Is the Coast of Britain? His attempts to understand why coastlines reveal ever more complexity the more closely you…