sentences:  In 1968 and after twenty years of construction, the I-40 opened a segment from the Tennessee state line to US 276, in Cove Creek.In November of same year, the North Carolina State Highway Commission submitted a request to the Bureau of Public Roads to extend I-40 east of Greensboro to Raleigh, via the Research Triangle Park (RTP).In 1969, both the Bureau and AASHTO approved the extension, allowing I-40 to continue east of Durham, through Raleigh to Smithfield.