Scuttle vent hose inside the car

Hello again, I have replaced the heating hoses and
drain hoses and now I cannot find where the scuttle vent hose goes to inside the car, this is the large hose size that comes from the vent inside the car to let fresh air in, I had a hose hanging from this vent but cannot fathom out where it would go to, I guess it just be lying behind the dash to let air circulate, can anybody confirm, (picture is of the scuttle vent inlet inside the car)

It just feeds air into the box surrounding the heater.

Thank you Pete
Much appreciated