abstract
after dark
autonomy
bar
barbed wire
barrier
black
blue
blur
border
boundary
cheerless
confinement
dark
depth of sharpness
detention
dismal
emotional
fence
forlorn
freedom
gaol
gloomy
grim
hope
hopeless
horizontal
impossible
imprisonment
independence
jail
jail guard
landscape
leeway
liberty
light
migration
mystery
no people
obstacle
orange
outdoors
outline
penitentiary
prison
sadness
sets
shape
silhouette
somber
sombre
sun
totalitarian
unfreedom