A Fortification In De Kastri Fortified Area (Russia)

This is how it looks during the day.

A gun-port.
A pillbox near Tigil Bay.
A pillbox near Cape Zeleny.
A caponnier near Cape Medvezhy.
An observation window.
Its rear view.
An armoured door.
Battery #931 at Cape Ostry. This is an entrance into the command post of the battery. In the distance you can see an observation post.
Observation windows.
The command post from the inside.
An entrance into the ammunition storage.
The storage.
A parapet.
This is probably an engineering and utility services room.

Location: Cape Ostry