After lengthy excavations, the ruins of this once grand sugar mill are accessible to the public. Dating from the early 1830s and sophisticated for its time, the mill belongs to the pre-industrial age and functioned primarily with slave labor. After ceasing production in 1890, the main buildings – a hacienda, a three-story bell tower, slave quarters and some cisterns – fell into ruin. Admission includes an informative tour in one of several languages, providing better insight than at other sites in the valley.
Renovation is ongoing and has been criticized by some who think the ruins should have been left as, well, ruins. San Isidro is accessed by branching right off the Trinidad–Sancti SpÃritus road, 10km east of Trinidad. It's a further 2km from there.