Interstate 45 is an interstate highway located entirely within the state of Texas, United States. Like other "interstates," it is commonly referred to as I-45. Its odd number indicates that it is primarily a north-south highway. Its southern end is in Galveston, Texas at Texas State Highway 124; its northern end is in Dallas, Texas at Interstate 30.
Unmarked I-345 in Dallas, Texas. I-345 is less than one mile long and connects the end of I-45 to the end of US 75 along the east side of downtown Dallas. Since there are no signs labeling it as I-345, most people assume that is part of I-45 or US 75.
Despite this, some highway mavens propose extending I-45 from there to Muskogee, Oklahoma, then to Vinita, Oklahoma, and then through east Kansas along US 69 all the way up to Interstate 35 (where the US 69 freeway currently ends) in the Kansas side of suburban Kansas City.
If I-45 is extended to Kansas City, it would seem to make sense to reroute I-35 onto I-29 and then have I-45 run up to Minnesota as I-35 currently does. This would make I-35 and I-45 both transcontinental interstates.