Much has been learned from the basin of the Candelaria River, Campeche, Mexico: the fabric of a densely settled pre-Historic landscape, including impressive ceremonial centers; the logistics of an ancient entrepôt; the process of exploitation of dyewood and chicle in historic times; as well as the doubtful results of the mid-twentieth-century colonization of an “empty” forested basin. It also yielded the first evidence of more or less intensive pre-Hispanic wetland agriculture in the Maya region and the remains of a profuse network of fluvial transportation from prehistoric times to the present. This article presents recent evidence regarding the management of the river system itself by means of barriers, or “dams,” which facilitated agriculture in the wetlands upstream and extensive canoe travel. These structures seem to be elaborations or imitations of the numerous natural barriers already in the stream. Two models help explain context and function. It has become apparent that the human interventions into the wetlands and the river system are to be seen less as great attainments of civilization than as fairly desperate expedients in the face of climate change.

Some prominent Mesoamericanists long considered lowland central Veracruz to have been agriculturally unproductive prior to the Totonacs' construction of a canal-irrigation system at Zempoala during the Middle Postclassic period (A. D. 1200-1400). This evaluation reflects a long-standing negative predisposition toward tropical lowlands and a preoccupation with the significance of canal irrigation in the emergence of urban societies. However, an appreciation of mesoenvironments and their ecological interrelations has led to a reevaluation of agriculture in central Veracruz. In wetlands to the south of Zempoala, evidence of canals and planting platforms supporting maize cultivation by A. D. 500 demonstrates that people were intensively cultivating that mesoenvironment by the Classic period (A. D. 1-850). Moreover, vestiges of sloping-field terraces occur throughout some 1,000 km2 of piedmont west of those wetlands. Direct evidence for crops and a chronology are still lacking for these latter fields, but ethnohistorical data and plant ecology suggest cotton, maize, agave, and a Prehispanic origin.

In the lowlands of Central Veracruz, as in various locations across the base of the Yucatan peninsula, Prehispanic agriculturalists sought out wetlands with a limited fluctuation in water level for adaptation to intensive cultivation. Vestiges of canals and raised fields show through the dry season pastures of many ranches. The rectilinear remains of the earlier incursion show considerable accordance, from wetland to wetland, in their astronomical orientation: about 15 degrees clockwise of our own cardinal directions. It may be hypothesized that this orientation was imposed from Teotihuacan and that the majority of the raised field vestiges seen in the wetlands of Central Veracruz date back at least to a time between A.D. 100 and 600.

Prehistoric ridged fields and canals were recognized from the air in 1968 along the Candelaria River of Campeche, Mexico, in the vicinity of sites described by E. Willys Andrews in 1943. These remains were subsequently identified by Scholes and Roys as the settlements of Acalan, a native province along the route of the journey by Cortes to Honduras. Ground exploration in 1969 and 1970 has suggested that the fields were used over a considerable period of time under a system of diversified horticulture. The extensive canal system apparently provided access from the rivers to firm ground and allowed shortcuts and bypasses alongside the rivers themselves. The landscape suggests a considerable prehistoric population, vigorously engaged in major public works projects over a large area. It invites further integrated investigation of its past human ecology, particularly for information on variants of basic Lowland Maya subsistence patterns and the new perspectives this may give on the structure, success and demise of this civilization. An earlier version of this paper was read at the 39th International Congress of Americanists in Lima, 1970.