This is a data module for : it supports miscellaneous icons for public transport in Athens, including those used by Transport for Athens since 2014.
, none of the organisations behind the construction or operation of the Athens Metro specify the exact line colour values for web or print, but they agree on a general colour scheme for identifying lines.
Colour and icon specifications, along with a list of sources used for its development, can be found at Template:Athens transit icons on the Wikimedia Commons.