The international E-road network is a numbering system for roads in Europe developed by the United Nations Economic Commission for Europe (UNECE). The network is numbered from E1 up and its roads cross national borders.
European route E20 runs from Shannon Airport, Ireland to Saint Petersburg, Russia. It runs roughly west–east through Ireland, the United Kingdom, Denmark, Sweden, Estonia, and Russia. Its length is 1,880 km (1,170 mi) but it is not continuous; at three points, a sea crossing is required.
