In this study, a total of 60 chestnut (Castanea sativa Mill.) wood samples were exposed to soil contact conditions for a period of three years in accordance with the EN252 standard. The tests were conducted in four provinces of Türkiye-Trabzon, Muğla, Çanakkale, and Elazığ-representing the Blacksea, Mediterranean, mixed, and terrestrial climate zones, respectively, in order to assess the natural durability of the wood under different environmental conditions. Climatic indices, soil characteristics, visual decay, mass loss, density, bending strength, modulus of elasticity, compressive strength, and color change were investigated. Among the four locations, the lowest average visual decay rating was observed in chestnut wood Elazığ (1.0), while the highest was recorded in this species of wood in Çanakkale (3.6). Similarly, the greatest weight loss occurred tested wood in Çanakkale, reaching 35.96%, whereas wood in Elazığ exhibited the least mass loss at 4.71%. Regarding density, wood in Elazığ presented the highest value at 0.54 g/cm³, whereas wood in Çanakkale showed the lowest at 0.39 g/cm³. The highest bending strength was wood in Elazığ at 71.73 N/mm2, the lowest was wood in Çanakkale at 38.28 N/mm2. The highest elastic modulus was wood in Elazığ at 5965.89 N/mm2, the lowest was wood in Çanakkale at 3855.42 N/mm². The highest compressive strength parallel to fibers (underground and aboveground) was wood in Elazığ at 48.25 N/mm² and 50.87 N/mm², respectively; the lowest was wood in Çanakkale, 13.51 N/mm² and 40.59 N/mm², respectively. The most significant color change was observed in the chestnut wood in Trabzon.