As Loriners will know Hephaestus was the patron god of metal working no doubt including the parts wrought in metal on a horse’s harness such as bits, bridles and stirrups. And as everyone knows the Greeks were riding horses more than a thousand years before the Birth of Christ.
The metro system in Athens is not complicated – just three lines: green, red and blue, as easy as one, two, three and indeed that’s what they are called.