From Arlington, I-20 passes into Dallas County at Grand Prairie and heads east in to Dallas, interchanging with I-35E south of downtown and I-45 shortly after. I-20 intersects with I-635 (where it completes a three-quarter loop around the city) on Dallas' southeast side before heading east toward East Texas. The Interstate varies from 4 to 10 lanes from its I-30 junction near Aledo to its US 80 junction near Terrell.
From Arlington, I-20 enters Dallas County at Grand Prairie and heads east into Dallas, switching to I-35E south of downtown and I-45 shortly afterward. I-20 meets I-635 (where it completes a three-quarter loop around the city) on Dallas' southeast side before heading east toward East Texas. The Interstate ranges from 4 to 10 lanes from its I-30 junction near Aledo to its US 80 junction near Terrell.