) ▁and ▁to ll s ▁were ▁then ▁removed ▁from ▁the ▁road , ▁which ▁the ▁next ▁year ▁was ▁officially ▁designated ▁as ▁Inter state ▁ 3 0 ▁( I - 3 0 ). ▁ ▁Const ruction ▁began ▁on ▁N T TA ' s ▁oldest ▁existing ▁to ll ▁road , ▁the ▁Dallas ▁North ▁T oll way , ▁in ▁ 1 9 6 6 , ▁and ▁its ▁first ▁segment ▁( from ▁I - 3 5 E ▁to ▁I - 6 3 5 ) ▁was ▁opened ▁in ▁ 1 9 6 8 . ▁The ▁T oll way ▁( as ▁it ▁is ▁popular ly ▁known ) ▁has ▁( al ong ▁with ▁general ▁Dallas - area ▁growth ) ▁expanded ▁contin ually ▁north ward , ▁opening ▁extensions ▁in ▁ 1 9 8 7 , ▁ 1 9 9 4 , ▁and ▁most ▁recently ▁in ▁ 2 0 0 7 . ▁ ▁T TA ▁started ▁construction ▁in ▁ 1 9 7 7 ▁on ▁its ▁first ▁to ll ▁bridge , ▁the ▁ ▁Mountain ▁Creek ▁Lake ▁Bridge , ▁which ▁opened ▁in ▁ 1 9 7 9 . ▁The ▁bridge ▁sp ans ▁Mountain ▁Creek ▁Lake ▁in ▁the ▁south western ▁Dallas ▁County ▁city ▁of ▁Grand ▁Pra irie . ▁ ▁Const ruction ▁was ▁started ▁on ▁T TA ' s ▁only ▁project ▁outside ▁the ▁area , ▁the ▁ ▁J esse ▁Jones ▁Memorial ▁Bridge ▁across ▁the ▁Houston ▁Sh ip ▁Channel , ▁in ▁ 1 9 7 9 , ▁with ▁the ▁bridge ▁opening ▁in ▁ 1 9 8 2 . ▁T TA ▁sold ▁the ▁bridge ▁to ▁the ▁newly ▁created ▁Harris