The sale of The Plas in Trimsaran marks the end of a significant chapter in the industrial and social history of Carmarthenshire. Once the seat of local influence and industry, The Plas stood at the heart of a vast estate that encompassed rich mining lands, industrial works, and agricultural holdings. This article explores the sale of its extensive assets—land, mineral rights, and industrial infrastructure—shedding light on the transformation of Trimsaran’s landscape and community during a time of economic and social change. Through archival material, personal recollections, and historical records, we trace the legacy of The Plas and its impact on the region.