The nation state promoted economic unity, by abolishing internal customs and tolls. In Germany, that process, the creation of the Zollverein, preceded formal national unity. Nation states typically have a policy to create and maintain a national transportation infrastructure, facilitating trade and travel. In 19th-century Europe, the expansion of the rail transport networks was at first largely a matter for private railway companies, but gradually came under control of the national governments. The French rail network, with its main lines radiating from Paris to all corners of France, is often seen as a reflection of the centralised French nation state, which directed its construction. Nation states continue to build, for instance, specifically national motorway networks. Specifically transnational infrastructure programmes, such as the Trans-European Networks, are a recent innovation.