sentences:  Several segments of U.S. 281 are concurrent with Interstate routes, including I-69C in the Rio Grande Valley, I-37 in San Antonio, and I-44 north of Wichita Falls.US 281 has two signed segments near its southern terminus in the Rio Grande Valley, both of which are signed west–east.The eastern segment, considered mainline US 281 by TxDOT, begins in Brownsville at an intersection with Business US 77 and SH 48 about from the Mexico border, and travels west through several communities along the border to Pharr.