Petit-Escalator, the shortest escalator in the world, is located in the basement of Kawasaki More's Department Store, across the street from Kawasaki JR station. Five steps and 83.4 centimeters in height, the escalator takes approximately eight seconds to deliver passengers from bottom to top.
The escalator connects the B2 level of More's with the Azalea underground shopping arcade, which is slightly less deep. Oddly enough, the escalator doesn't cover the entire vertical distance between More's B2F and the arcade - you have to climb several steps before you get to the starting point of the escalator.
The easiest way to get there is to descend into the Azalea arcade at the entrance right in front of JR Kawasaki Station, then look for exit #29. Alternatively, you can look for the More's building at ground level and then go down to the B2 level.
The escalator is listed in the Guinness Book of World Records, and it has its own official web page.