sentences:  The "Urban Planning Study for Piraeus" (451 BC), which is considered to be a work of Hippodamus, formed the planning standards of that era and was used in many cities of the classical epoch.According to this study, neighbourhoods of around 2,400 m2 blocks were constructed where small groups of 2-floor houses were built.The houses were lined up with walls separating them while the main facets were towards the south.