Underground Escalator

An escalator is a moving staircase which carries people between floors of a building or structure. It consists of a motor-driven chain of individually linked steps on a track which cycle on a pair of tracks which keep them horizontal.Escalators are often used around the world in places where lifts would be impractical, or they can be used in conjunction with them. Principal areas of usage include department stores, shopping malls, airports, transit systems (railway/railroad stations), convention centers, hotels, arenas, stadiums and public buildings.escalator, moving staircase used as transportation between floors or levels in subways, buildings, and other mass pedestrian areas.It is still an "elevator". For that matter, what do you call stairs (you can go up or down them). If you have a pair of staircases, one designated up and one down, you might differentiate the "down" staircase. But you would do it by adding a clarifying label, there isn't a different term. – fixer1234.