Within Mexican national territory it would be difficult to find a piece of land without an owner, or which is not under the jurisdiction of an individual or an institution. For this reason, in discovering or rediscovering archaeological sites archaeologists are also discovering property systems and land use rights associated with the places those sites are found. Clusters of monumental structures, public spaces, and areas of everyday or domestic use need to be understood in terms of their relationships to each other and to the places which surround them. Nevertheless, once abandoned, whether previously monumental structures, modest dwellings, or cultivated fields, their previous value and significance may largely disappear with the subsequent arrival of new owners or users. These then adapt, displace, or ignore the vestiges of previous use.
We know that the residential and agricultural areas of pre-Columbian Mitla and Monte Alban began to have new uses in the colonial period, if not before. The founding of San Juan Chapultepec as a "Pueblo be Indios" (Indian community) on the lower slopes of southeast Monte Alban dates back to 1523, at the very beginning of the colonial period (Taylor 1990: 159). There exists a map from 1760 which clearly shows this settlement on the slope leading up to the pre-Columbian city. In the case of Mitla the history is similar, as with the construction of the colonial religious structures on the pre-Columbian palaces and temples (Robles, et al, 1987; Robles and Moreira 1990) the latter lost their sacred character. Buildings were destroyed and their spaces began to serve other uses. In the middle of the nineteenth century the pre-Columbian buildings were still outside the community (Magadan 1984: 195). But the boundary the river posed for urban growth lasted only until the end of the century, when urban sprawl began to pass this natural barrier to expand toward the monumental zone, as may be seen in a map made by Batres in 1900 (Figure 9).
For the contemporary communities surrounding both sites the monumental and lesser spaces are totally susceptible to some use, whether this is for cultivation, residence, grazing, extraction of materials, or some other use. For this reason those responsible for managing collective tenure systems began to divide these spaces into communal lands, ejidos, or even private property on some occasions. For both sites the presence of nearby human settlements poised a latent threat in that some day population growth or new uses would generate increased pressures on the land. And in fact a variety of information sources, from aerial photographs, old maps, and ground surveys, show this is what has happened.