Abstract The beginning of the concept of architectural monument in Colombia is in the laws from the late XIX century and early XX century. We recompose the international context through the technic of aero photography, used by the Military Geographical Institute during the Second World War and the consequent tensions between U.S. and the powerful nations of the axis in relation to Colombia and Brazil in Latin America. The Liberal Party emerges like an ideology that tried to reorganise the country through the establishment of education and control the soil. This party negotiated a pact to stop the Colombian-Peruvian war 1932-1933, and signed the Roerich Pact in 1935 to protect the monuments. Therefore, the 1942 plan is the end of a process of mapping the national territory and the generation of criteria about cultural heritage in the first half of XX century, and the base to study how it affected the protection of architectural monuments up to date.