The station has undergone a number of transformations. During the Erie period, the station was so busy that a second platform was added to manage the flow of passengers from the over 30 passenger trains that ran in and out of the station hourly. The desire to reuse old caissons (from previous tunneling attempts) when building the H&M system meant that the tubes at this location were far inland. As a result, the actual station was not closely integrated into the Erie Railroad Terminal above, and the Erie never built a new terminal on top of the underground platforms. Therefore, a lengthy walk through inclined pedestrian tunnels was necessary in order to connect from the H&M to the passenger trains. In response to this, in 1954, the Hudson and Manhattan Railroad installed a long moving sidewalk known as "the Speedwalk". It was the first such moving walkway built in the United States; built by Goodyear, it moved up a 10 percent grade at a speed of 1.5 mph (2.4 km/h). The walkway was closed within a decade due to significant changes happening above ground. It remained in place until the mid-1990s when the station was completely refurbished in response to the new office and commercial development in the area.