The Gateway tradition refers to a set of archaeological sites within western Montrose and San Miguel Counties, Colorado, that appear similar to Pueblo II–period (AD 900–1150) sites to the south in the core homeland of the Ancestral Puebloans (Figs. 1 and 2). The sites in Montrose and San Miguel Counties, however, lack key diagnostic attributes of Pueblo II–period Ancestral Pueblo sites, such as kivas and a highly patterned layout of habitation structures, plazas, and refuse deposits. Archaeologists in the region have attributed the sites to the Ancestral Puebloans, the Fremont, and to local groups that adapted traits of both. Recent reanalysis of archaeological materials excavated at the Weimer Ranch site complex northwest of Norwood, Colorado has provided convincing evidence that the Gateway tradition represents a short-term incursion of Ancestral Puebloans into west-central Colorado.

History of the Gateway Tradition Concept

Early archaeological investigations in southwestern Colorado focused on Ancestral Puebloan sites south of the San Miguel Mountains in the San Juan River drainage. Although a few sites with masonry architecture reminiscent of Ancestral Puebloan sites had been reported north of the San Miguel Mountains, most of the archaeological sites there were known to be stone artifact scatters without apparent architecture or pottery. The region was considered to be outside of the main homeland of the Ancestral Puebloans.

The Colorado State Historical Society conducted some of the first archaeological excavations in the area north of the San Miguel Mountains in 1924, focusing on several noncontiguous, rectangular masonry rooms in the Paradox Valley in western Montrose County. The investigators concluded that the structures represented Ancestral Puebloan summer homes, based on the nature of the architecture and pottery.

Further excavations in the 1930s and 1940s, focusing on the larger architectural sites, produced Ancestral Puebloan pottery types. The revealed architectural styles, however, were not entirely compatible with those of Ancestral Puebloan sites located south of the San Miguel Mountains. The sites contained no kivas, which are nearly universal at Pueblo-period habitation sites in the Ancestral Puebloan homeland. The typical pattern of Ancestral Puebloan site layout, with surface habitation structures at the northern end of the site; a plaza and subterranean kiva just south of the surface habitation structures; and a midden, or refuse deposit, at the southern end of the site was not evident at the excavated sites in western Montrose County. In a review of these various archaeological investigations, Albert Schroeder concluded that the sites represented a northward expansion of either Pueblo II–period Ancestral Puebloans or aspects of their ways of life.

After a thirty-year hiatus in archaeological excavations in San Miguel and western Montrose Counties, Metropolitan State College in Denver commenced an excavation project at ten structural sites on the Weimer Ranch. Excavations revealed rectangular and circular rooms, evidence of corn, stone arrow points, and pottery. The pottery was classified into Ancestral Puebloan types, essentially indicating a Mesa Verde–region ceramic assemblage. The pottery was thought to represent Ancestral Puebloan types, but the circular masonry structures and aspects of site layout were more similar to the Fremont culture. Thus, investigators suggested that the Weimer Ranch sites were occupied by an indigenous group that borrowed elements of both Ancestral Puebloan and Fremont cultures.

Meanwhile, archaeological surveys attributed structures on some sites to the Fremont. This trend intensified when Utah archaeologists suggested that cultural variation was one of the defining characteristics of Fremont sites.

In 1997, Alan Reed coined the Gateway tradition as a way to describe sites in west-central Colorado with pottery, evidence of corn, and masonry architecture. The tradition was defined to mark the region’s sites as substantially different from those of either the Ancestral Pueblo or the Fremont core areas. Fremont ceramics were believed to be rare in the region, and other key elements of the Fremont—such as one-rod-and-bundle basketry, moccasins made from the hock of a deer or mountain sheep, clay figurines and rock art depictions of trapezoidal figures with elaborate ornamentation, and a distinct ceramic tradition—were not known from the area.

The widespread presence of round masonry habitation rooms and the absence of kivas and highly patterned site layouts argued against direct affiliation with the Ancestral Puebloans. Furthermore, it seemed clear that full progression of Ancestral Pueblo culture—as represented by the Basketmaker III, Pueblo I, and Pueblo III archaeological units—was not represented in west-central Colorado. The Gateway tradition sites were thought to represent a local development that adapted elements of the farming-based cultures living to the south and west.

Recent Insights into the Gateway Tradition

In 2006 archaeologists completed a reexamination of the Weimer Ranch materials with funds provided by the Colorado State Historic Fund. Site maps, photographs, and basic architectural descriptions were compiled. Stone, bone, and pottery artifacts were analyzed and organized. Eleven radiocarbon dates were processed, including five dates produced by accelerator mass spectrometer (AMS) dating, a different type of radiocarbon dating.

Perhaps most important, the ceramic artifacts from the Weimer Ranch sites were submitted to Lori Reed, an expert in prehistoric pottery of the Four Corners area. The sample of 250 Ancestral Pueblo pottery fragments revealed types commonly dated between AD 900 and 1100—the Pueblo II period. The ceramics were attributed to three manufacturing locales, based on temper materials, paste characteristics, and slip. Some of the fragments were evidently manufactured in the Northern San Juan River drainage—the general vicinity of the Four Corners. A second set of pottery fragments was outwardly similar to the Pueblo II_­ period ceramics from the Northern San Juan area, but displayed subtle differences. Lori Reed suggests that this set of pieces was produced near Weimer Ranch.

Largely as a result of the Weimer Ranch reanalysis, it now seems likely that the Gateway tradition represents an actual incursion into west-central Colorado by Ancestral Pueblo peoples from the Northern San Juan drainage. These people either brought pottery from the Northern San Juan drainage with them or obtained it through trading networks. Once settled in west-central Colorado, they continued making their familiar pottery types using local materials. Possibly because their new communities were small, kivas were unnecessary. Round masonry rooms, where present, may have been constructed if little village growth was anticipated.

Dating the Gateway Tradition

The Gateway tradition is currently dated between about AD 900 and 1030, though the sample of high-quality AMS dates is small. The sample of AMS dates and ceramic types from various sites suggest that the Gateway tradition may have been of relatively short duration and limited to the Pueblo II period.

Settlement Patterns and Distribution

Although early researchers mention a few masonry sites with Puebloan ceramics on the eastern side of the Uncompahgre Plateau, the large majority is on the lower western flanks of the Uncompahgre Plateau in the San Miguel and lower Dolores River drainages. This area includes western Montrose County and northwestern San Miguel County (Fig. 1). Sites are generally clustered between 6,600 feet (2,011 m) and 7,100 feet (2,164 m), probably within the elevation zone where corn horticulture was possible during the time of occupation. Sites often occur on canyon rims. Structural sites appear to have between one and seven rooms. One of the more elaborate multiroom structures is Cottonwood Pueblo (Fig. 3).

A few Gateway tradition sites are located in relatively high elevations. Situated at 9,560 feet (2,914 m), the Jeff Lick site and its four or five circular structures may represent a summer or fall base camp and outpost for storage of plants and animals procured atop the Uncompahgre Plateau. The Fallen Deer site is a nonstructural site at the southern end of the Uncompahgre Plateau with Pueblo II–period ceramics at 8,160 feet (2,487 m). It, too, probably represents foraging trips above the farming belt.

Subsistence

The available subsistence data suggest a strategy based on corn horticulture. Wild plants were also important, however, and included grass seeds, pinyon nuts, juniper berries, acorns, cactus pads, and goosefoot seeds. Hunting was important, especially of deer. Bones of reptiles, small birds, rodents, rabbits, hares, elk, bison, bighorn sheep, and bears have also been recovered at Gateway tradition sites. Bones are frequently heavily processed, suggesting extraction of bone grease.

Technology

Gateway tradition stone-working and ceramic technologies are generally similar to those of the Northern San Juan area. Projectile points are dominated by small corner-notched varieties that are thought to have been arrow tips. Pottery from the Northern San Juan River drainage was brought to sites in west-central Colorado, but similar pottery styles were also locally manufactured. Whereas two-hand manos, or grinding stones, are common in the Northern San Juan area, they are uncommon in west-central Colorado. At Weimer Ranch, 97 percent of the recovered manos were of the one-hand variety. This suggests that corn milling may have been less intensive at Weimer Ranch than at contemporaneous sites in the Northern San Juan drainage.

Conclusion

Although the suspected origins of the people represented by the Gateway tradition has changed in light of new archaeological information, the tradition continues to be a useful way to think about local variation in the archaeological record. Even though the tradition probably represents a Pueblo II–period phenomenon, Gateway tradition sites do vary from contemporaneous sites in the Four Corners area. The Gateway tradition should prove useful for future studies of Ancestral Puebloan migrations, interactions between immigrant farmers and indigenous hunter-gatherers, defensive strategies, mechanisms of social integration, and aspects of technology that directly reflect cultural affiliation.