Making two meanders as it flows in a southeasterly direction, the river parallels the interstate and Riverside Drive then crosses under the interstate and California State Route 110 as it flows east of Elysian Park. It then receives the Arroyo Seco, another major tributary, from the left. The river flows south past the Mission Junction, a large railroad yard on the left. It enters a wider concrete channel with sloped sides, and crosses under Cesar Chavez Avenue, Highway 101, and Interstate 10 as it passes east of downtown Los Angeles, flowing past the East Los Angeles Interchange for Highway 101, California State Route 60, and Interstates 5 and 10 on the left. It then makes a gradual turn east and then turns southeast, flowing a few miles before it begins to parallel Interstate 710 near Maywood, Bell, Cudahy, and Commerce, from the mouth.