There were two initial trans-Texas corridors under consideration: One would have paralleled Interstate 35 (I-35), from Gainesville to Laredo and passing the Dallas-Fort Worth Metroplex, Austin and San Antonio. The other would have been an extension of the proposed I-69 corridor, generally following US 59, from Texarkana past Houston to either Laredo or the Rio Grande Valley. Both of these corridors have seen large increases in freight traffic demand over the past two decades due to increased trade with Mexico.
