Proposed high-speed rail by country

This is a list of planned, or proposed, high-speed rail projects by country. Although a number of countries have conducted preliminary feasibility studies, many lines are eventually shelved or postponed due to high costs; only a few nations are building high-speed rail lines. Planned (or proposed) lines are separated here from lines under construction, and some countries have both. High-speed rail is public transport by rail at speeds over 200 km/h (125 mph).