The Palouse Canyon Archaeological District, situated along the rugged canyon of the lower Palouse River in Franklin and Whitman counties, Washington, is a highly significant cultural landscape that documents over 10,000 years of continuous human occupation. This deeply incised canyon served as a vital transportation corridor and a rich resource zone for Native American populations, most notably the Palus (Palouse) people. The district encompasses a dense concentration of archaeological sites, including deeply stratified rockshelters, open-air campsites, tool manufacturing workshops, burial sites, and rock art panels featuring pictographs and petroglyphs. These resources are intimately tied to the seasonal rounds of the region's indigenous inhabitants, who utilized the canyon's unique microclimate, abundant fish runs, and diverse plant and animal life.

Listed on the National Register of Historic Places in 1984, the district holds immense scientific and research value for understanding the prehistory and ethnohistory of the Columbia Plateau. The exceptionally well-preserved archaeological deposits within the canyon's dry rockshelters have yielded critical data on technological transitions, such as the evolution of stone tool technologies, as well as trade networks and subsistence strategies over millennia. By preserving a comprehensive record of human adaptation to changing environmental conditions from the early Holocene through the post-contact era, the Palouse Canyon Archaeological District remains a cornerstone for archaeological inquiry in the Pacific Northwest and a sacred landscape of profound cultural importance to contemporary Native American tribes.

The Savage Island Archeological District, listed on the National Register of Historic Places in 1976, is a highly significant cultural resource area located along the Hanford Reach of the Columbia River in Franklin County, Washington. Centered on Savage Island, the district encompasses a remarkably preserved riverine environment that served as a vital cultural, spiritual, and economic hub for Indigenous peoples of the Columbia Plateau for thousands of years. Because the Hanford Reach remains the last non-tidal, free-flowing stretch of the Columbia River in the United States, the archaeological resources within this district escaped the permanent inundation and destruction caused by the massive hydroelectric dam projects that submerged similar cultural landscapes elsewhere along the river corridor.

Archaeological investigations within the district have revealed an exceptionally rich record of pre-contact Native American occupation, representing both seasonal resource-procurement camps and dense, semi-permanent winter villages. The sites contain well-preserved cultural features, including subterranean pit house depressions, hearths, shell middens, and extensive lithic scatters that reflect the complex subsistence strategies, salmon-fishing technologies, and seasonal rounds of the Wanapum and other Sahaptin-speaking peoples. These materials provide invaluable data regarding Plateau settlement patterns, trade networks, and environmental adaptation spanning several millennia. Today, the Savage Island Archeological District stands as a crucial monument to the enduring heritage of the region's First Nations and remains a vital locus for understanding the deep history of the Columbia Basin.