The East Los Angeles Interchange is an interchange complex located in Boyle Heights, Los Angeles, approximately 1 mile east of Downtown Los Angeles. With its southern portion handling over 550,000 vehicles per day, it is the busiest freeway interchange in the world. The northern portion, called the San Bernardino Split, is often considered a separate interchange. Four numbered routes converge at the interchange: Interstate 5 (I-5), I-10, U.S. Route 101 (US 101), and State Route 60 (SR 60), but the freeway segments shift alignments and directions.

Interstate 5 (I-5) is a major north–south route of the Interstate Highway System in the United States, stretching from the Mexican border at the San Ysidro crossing to the Canadian border near Blaine, Washington. The segment of I-5 in California runs 796.77 miles (1,282.28 km) across the length of the state from San Ysidro to the Oregon state line south of the Medford-Ashland metropolitan area. It is the longest interstate in California, and accounts for more than half of I-5's total length.