Nice site! Two small suggestions: when hovering over the icons, the mouse cursor should change to indicate that they are clickable. And, without being very familiar with the Silk Road, I imagine Tehran, Esfahan, Baghdad, Basrah etc. were also significant stations on the Silk Road, although it's currently not easy (or advisable) to visit them as a tourist - but I think they should still get icons...
The journey starts in Constantinople and from there branches out where you can choose where to travel, with all roads leading to the end in Eastern China. Hope you find it interesting and would love any input or suggestions for the project, as there are plenty more places to chart.