The three of us walked down the cement ramp into the gut of the city. Ducking beneath a security boom and camera, we went to the nearest wall and slid aside the enormous grille vent. Access granted.
Looking up, we can see the point where underground stops and city surface begins.
The small concrete cavity acts as a corridor and following it takes us only further down.
The bookstand presents itself...
...And brings us to the jet room.