Ross was very rich and based on his European background, he bought a 300-hectare piece of land and named it ""La Posada"" (), or Petren Fund, in 1885. Ross designed an urban place of high environmental value and landscape, turning ""La Posada"" into a hotel ("Great Hotel Pichilemu", later "Hotel Ross", or "Ross Hotel"), and building a casino, embankments, stone walls, a balcony facing the beach. Additionally, he built a park and a forest of more than 10 hectares. Agustín Ross turned Pichilemu into a summer resort town for the people from Santiago. Some of his buildings were named National Monuments.