The photo shows a border crossing between Spain and Portugal. Fractal pioneer Benoit Mandelbrot tells how a Spanish encyclopedia claimed that the length of the common border between Spain and Portugal is 616 miles, while a Portuguese encyclopedia quoted 758 miles. How could there be such a difference? It turns out that the measured length depends on the length of the measuring stick. The smaller the unit of measurement, the longer the determined length. In fact, in the limit, the length of this common boundary is infinite!
