Temple of Hephaestus-Ancient Agora

The Temple of Hephaestus in central ancient Athens, Greece, is the best-preserved ancient Greek temple in the world, but is far less well-known than its illustrious neighbour, the Parthenon. The temple is also known as the Hephaesteum or Hephaesteion. It is sometimes called the Theseion (Greek: Θησείο, thisio), due to a belief current in Byzantine times that the bones of the legendary Greek hero Theseus were buried there; in fact the bones alleged to be those of Theseus were buried in the 5th century BC at another site nearer to the Acropolis.
Source: Wikipedia