2. Tunnel into Penn Station, Hudson Yards

Penn Station-Amtrak Tunnels-Manhattan Schist-Exposed-Bedrock-NYC (1)

When trains enter Penn Station from the north or west, they take one of the tracks within Hudson Yards to enter the station. If you keep on the lookout through this dark corridor, packed with train infrastructure and equipment, you’ll see outcroppings of Manhattan schist that were never cleared away.