This is one of several vehicle tunnels in the area.  The curved tiled walls are standard for the longer vehicle tunnels in the area.  They are similar to the tiled tunnels you may see around New York, Philadelphia, and Baltimore. Virtually all of the vehicle tunnels have ceiling lights.  This one has a walkway for a patrolman and a booth about halfway through for observing traffic. 
This scene is in Crows Nest. To the left is the scenic overlook snack bar with restrooms.  You'll want to make a stop before entering the tunnel leading West to the (unfinished) village of Blessing.  
Return to Friendship Heights West view photo index