A geoarchaeological study of the large Essentuksky 1 kurgan in the Stavropol region of Russia analyzed the chemical composition and micromorphological features of the kurgan's earthen materials and established their relationships with buried soils in the context of previously conducted paleoclimatic reconstructions. The kurgan was 5.5-6.0 m high and more than 60 m in diameter, and consisted of four earthen and three stone constructions. It was built in the second quarter of the 4th millennium BC (the Early Maykop culture) using a precise plan and utilizing the building skills and technologies available at that time. The earthen constructions consisted of alternating layers of dark-colored slightly compacted humified and pale-colored dense carbonate-rich materials, which, in the moist state, were rammed down by ancient builders. These materials were sourced mainly from local soils and contained admixtures of river silt and, at the final stage of building, dung. The physicochemical properties of the earthen constructions as well as the paleosols buried under them are indicative of a short-term aridization of the climate within the period of building. A gleyed earth with strong iron staining at the kurgan's base and mortar that held the stone constructions was produced by thoroughly mixing and compacting in a wet state, indicating that they were special construction materials. This kurgan is an example of the ancient earth architecture in the steppe zone of Russia over 5500 years ago.