 With approximately 122,000 workers and 103,000 residents, Cumberland is the region's fifth-largest business district, and is marked by several modern skyscrapers rising from the wooded hills above the freeways.It is situated ten miles (16 km) northwest of downtown Atlanta at the junction of I-75 and I-285 (the "Cobb Cloverleaf") in Cobb County.Although small portions lie within incorporated Smyrna, the majority of the area is unincorporated and shares ZIP code 30339 with the Vinings area, which the United States Postal Service considers to be unincorporated Atlanta.