Ключевые слова: arrow, background, change, communication, concrete, construction, control, crossing, curve, design, direction, future, gravel, industry, infrastructure, iron, junction, line, management, metal, mock up, nature, outdoor, parallel, pattern, point, rail, railroad, railway, road, rock, route, safety, sleeper, speed, steel, stone, structure, switch, technology, ties, track, traffic, train, transport, travel, two, way,