Trefethan's winery was originally built back in 1886 at the center of Eshcol Ranch. The winery was built as a gravity-flow winery, where grapes were crushed on the third floor, fermented on the second, and aged on the first, utilizing the gentle force of gravity to move from one stage to the next. The Trefethan's purchased the winery in 1968 at a time when the old Eshcol facility had slipped into serious disrepair. The facility has seen two major renovations as an earthquake almost leveled the facility. The Eshcol label now rounds out the Trefethen portfolio as an introduction to their estate grown and sustainably produced wines.