This is how you get in Mustek metro station. Mustek is one of the busiest stations in Prague. Two lines (green and yellow) meet here. It has its entrances in Narodni trida street and several at Wenceslas square. So it's pretty in the center of Prague.
We used to play on these steps (are they called escalators in English?) in the days of elementary school (which is very close to Mustek). We took a paper from an excercise book, shape it in the shape of a car and sent it down on the slipway between the steps. It was very funny. Running down to cach the car - they did fly up, often - and then running up to send it down once more. I know I did a poor job in explaning this "game", but I tried, at least :)