State Route 905 (SR 905), also known as the Otay Mesa Freeway, is an 8.964-mile-long (14.426 km) state highway in San Diego, in the southwestern part of the U.S. state of California. It connects I-5 and I-805 in San Ysidro to the Mexican border at Otay Mesa. The entire highway from I-5 to the international border is a freeway with a few exits that continues east from the I-805 interchange before turning southeast and reaching the border.

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.