Interstate 45 (I-45) is a major Interstate Highway located entirely within the U.S. state of Texas. While most Interstate routes which have numbers ending in "5" are cross-country north–south routes, I-45 is comparatively short, with the entire route located in Texas. Additionally, it has the shortest length of all the interstates that end in a "5". It connects the cities of Dallas and Houston, continuing southeast from Houston to Galveston over the Galveston Causeway to the Gulf of Mexico.

Downtown Dallas is the central business district (CBD) of Dallas, Texas, United States, located in the geographic center of the city. It is the second-largest business district in the state of Texas. The area termed "Downtown" has traditionally been defined as bounded by the downtown freeway loop, bounded on the east by I-345 (although known and signed as the northern terminus of I-45 and the southern terminus of US 75, on the west by I-35E, on the south by I-30, and on the north by Woodall Rodgers Freeway.