Ninety percent of the world's amber comes from a mine in Kaliningrad on the Baltic Coast and from there it is exported around the world. Not only is amber beautiful - it can also contain insect time travellers trapped inside. But the appeal of amber is not new. Nero loved amber and sent emissaries north to bring amber back to him. This route is now recognised as a historic trail you can follow, as author, cartographer and amber lover CJ Schuler did.