The 400-year Han Dynasty (actually two dynasties with the same name, separated by a few years of chaos) was a wellspring of innovation and advancement.

Chinese scientists invented the compass and the first really accurate grid-based maps, but the Chinese didn't always use their inventions in ways you may think of as obvious. At first, instead of using the compass as a navigational device, the Chinese thought the compass was a dandy tool for making sure that temples were built on the proper, sacred alignment.

Still, these guys were way ahead of their time, especially when you consider that they put efficient rudders on ships back when Romans and barbarians still steered by sticking a big paddle in the water at the back of the boat.