On a table or a table with a sloped channel in the middle, a bag was placed containing whole, ripe olives. Men wearing wooden clogs or special shoes, trod repeatedly on the sack of olives, supporting themselves on ropes that hang from the ceiling. Once the pulp was free from the stone, the bag was refilled with hot water and the task of treading on the bag was resumed. This operation was repeated several times to extract as much juice as possible. The oil was decanted in jars or bowls.
This procedure was used in ancient times and was still in use at the beginning of the century in small farms in areas of the Mediterranean with little or no technological development.
The trodden system was widely used in antiquity for the extraction of olive oil.
Source: Pieralisi España S.L