The top floor corridor has a slanting glass wall to one side. It lets light down into the lower corridor, which would otherwise be very dark.
The fitting at the edges between panes needs to be seamless (or as near to as possible), and the glass has to be maximum strength to be able to support the weight of people falling on top of it. It should be extra thick (several inches) and blast-resistant.
Sketch of work here.
The New Shed 