Monsanto Forest Park an auditorium, a space for permanent and occasional exhibitions, and a Centre of Multimedia Resources. Quercus, the largest Portuguese non-profit national environment organization for the conservation of the natural environment, is based in Monsanto Park. The intensive agricultural usage of the soils led to erosion and practically to a destruction of the original vegetation. In the 1930s, the increasing demand for construction areas led Duarte Pacheco, the then Minister for the Public Works of Portugal, to resuscitate an idea from 1868: the reforesting of the then practically bare Serra de Monsanto. The regulation for Monsanto Park was put in place
Castle of Monsanto an unknown commander. As a result of this change, in 1174, a new foral was issued to the inhabitants of Monsanto, by D. Afonso Henriques, which was confirmed in 1190 by D. Sancho I. A contemporary castle was constructed during the 13th century. It was reconstructed in the 14th century, during the reigns of King D. Dinis and D. Fernando. But, following its alignment with the Kingdom of Castile during the 1383–1385 Portuguese interregnum, the site began to fall into disorder. According to the chronicler Fernão Lopes, Monsanto was a village that had been loyal to Queen Beatrice. But, later