abstract
art
background
barb
barbed
barbwire
barrier
black
boundary
camp
concepts
copy space
crime
criminal
danger
dark
defense
dreams
fence
free
freedom
gloomy
heavens
hope
hopelessness
horizontal
jail
liberty
monochrome
nightmare
obstacle
oppress
overcast
pale
prison
private
problems
protection
refugees
rusty
secure
security
shadow
silhouette
sky
twisted
upwards
wall
war
wire