Interstate 35 or I-35 is a highway that passes right through Lil' D. It merges in Denton from I-35 West (which passes through Fort Worth) and I-35 East (which passes through Dallas). It continues as I-35 into Oklahoma.

This division into east and west confuses some newcomers to Denton, who try to take I-35 south and suddenly have a choice between two of them. This can be quite traumatic and has also resulted in numerous accidents over the years as distracted (also known as Texas) drivers come to a complete stop in the left lane in an attempt to cut over to the exit at the last possible second.

35 Denton, the annual music festival, is named after I-35.