Hacienda Llanda was established ca. 1885 as a 250 cuerdas plantation by Spanish immigrant from Sóller Ramón Frontera Pons (1851-1935) who arrived in Puerto Rico in 1865, and his wife Maria Luisa Maristany Agostini.   Frontera Pons was a resident and prosperous merchant in Maricao where he operated the firm Frontera Hnos. together with his brother Amador.   In addition to Llanada, he owned Haciendas Balear, Santiaga and Unión, all in Maricao.  Shortly after establishing Hacienda Llanada, his nephew Antonio Frontera Rullán, born in Sóller in 1870 the son of Amador Frontera Pons and Maria Rullán Frontera, was made responsible for the administration of Hacienda Llanada.

Sometime after 1890 Antonio Frontera Rullán and his wife Maria Marroig Bernat (1875-1971) who was also born in Spain and died in Puerto Rico, acquired Hacienda Llanada from his uncle and continued to run it with their son Francisco Frontera Marroig (1899- ).  By 1920 they acquired 99 cuerdas part of Hacienda Bonifacio of Jaime Miró which today lie on the  West side of PR-426, ca. 1926 they acquired 80 cuerdas part of Hacienda Esperanza of Indalecio Rodriguez and in the 1940s acquired the 92 acre Hacienda Fortuna from Juan Alvarez Menéndez and his wife Julia Massini de Jesús.  Antonio returned to Spain in the early 1930s leaving the plantation to his son Francisco Fronterra Marroig who had married Idolina Aymat Frontera the daughter of José Aymat owner of Hacienda Dolores.

The real development of Hacienda Llanada was between 1920-1950 under the ownership of Francisco Frontera Marroig, way after the coffee industry boom which lasted until ca. 1902. ​  It is located on the East side of PR-426 at Km 3.

The aerial picture in the first gallery below is made available by permission and the courtesy of Archeologist Luis Pumarada O'Neill.  The other pictures are part of a 1987 study made by Archeologist Luis Pumarada O'Neill.  Source: Puerto Rico State Historic Preservation Office.