background
business
car
cargo
caution
conceptual
construction
control
crossing
danger
departure
electrical
equipment
illuminated
industry
infrastructure
iron
journey
junction
light
line
metal
nature
public
rail
railroad
railway
red
road
safety
semaphore
sign
signal
station
steel
stop
stoplight
symbol
symbolical
track
traffic
train
transport
transportation
travel
urban
wait
warning
way
winter