Strand Millas and Rock Spring is a historic home located near Montchanin, New Castle County, Delaware. The name "Strand Millas" is derived from an industrial town near Belfast, Ireland. The Strand Millas house was built in 1701, and is a 2+1⁄2 story, quarried stone dwelling. It was expanded with one room on each floor during the 1760s. Strand Millas was the home of du Pont heiress Louisa d'Andelot Carpenter after her marriage in 1929.