Regarding its history, the available documentary sources are only a few. Its name comes from its former ownership by the Order of St. John (Spanish, San Juan), whose encomienda was placed in Tocina during the Late Middle Ages. The support of the Order of St. John's knights to the conquest of Lower Andalusia during the 13th century would be rewarded with an important number of awards by the Castilian Crown; among them, this Mill, which would start to be known as "de San Juan" (St. John's). This fact is documented within the distributions made by King Alfonso X in 1253, when the Order of St. John's knights were granted "two wheels of mills with its weirs on the Guadaíra [River]", one of which would be probably the present location of San Juan Mill.
The present-day building is the result of the medieval original mill transformations carried out between the 17th and the 20th centuries, so little remains from the original one. The great squared- plant tower stands out; it was used like a store before the river's floods. If we look in the downstream direction, we find a building, the access to the mill and the area for grain and freshly ground flour load and download.
Over the stream the stone building is placed, covered by a barrel vault; under it there are the buckets, they are four. The great weir that is connected to Guadaíra's left bank was widely re-built in 1998.
Over the level of flooding, on the right bank, you will find the Miller's House, a single building of rectangular floor-plan used like house and store until the end of the miller cycle, by mid 20th century.