3. The Glass Walkways

While most people will recognize the signature glass windows of Grand Central Terminal‘s atrium, many may be surprised to know that those windows contain walkways. The catwalks that run across the massive windows connect offices so employees do not have to fight through the crowds within the station to get where they need to go. A special key and a bit of nerve are required to gain access and traverse the elevated glass pathways. You can see photos from Untapped Cities’ visit inside here!