Greek road sign K-2a (K-2α) according to road traffic codex 2009 (KOK 2009).Meaning: Dangerous two opossing or continouous curves, the first to the left.  This sign was enacted in 1974 by the Greek Goverment Gazzete Sheet ΦΕΚ Β' 676/74.
Own work
Christaras A