According to Plato: "The dockyards were
filled with triremes and their appropriate equipment... and a
large harbor and canal were constantly crowded by merchant
vessels and their passengers arriving from all quarters, whoes
vast numbers occasioned incessant shouting, clamor, and general
uproar, day and night." - CRITIAS Dialogue / 117.e
"...they quarried beneath the whole central islet and outer
and inner rings, thus, by the same process, excavating a pair of
interior basins for shipping with a roofing of native rock."
- CRITIAS Dialogue / 116.b