Interstate 64 (I-64) passes through the Greater St. Louis area in the US state of Missouri. The entire route overlaps U.S. Route 40 (US 40). Because the road was a main thoroughfare in the St. Louis area before the development of the Interstate Highway System, it is not uncommon for locals to refer to the stretch of highway as "Highway 40" rather than "I-64". On December 6, 2009, the portion of the highway running through the city of St. Louis was named the Jack Buck Memorial Highway in honor of the late sportscaster.