Ключевые слова: alert, background, barrier, blinking, blue, caution, cross, crossing, crossroad, danger, direction, flash, gate, industry, infrastructure, journey, landscape, light, line, locomotive, metal, outdoor, pole, rail, railroad, railway, red, road, route, safety, semaphore, sign, signal, signpost, siren, sky, speed, station, steel, stop, street, symbol, track, traffic, train, transportation, travel, warning, way, white,