As it passes through many of Los Angeles' eastern suburbs in southern San Gabriel and Pomona valleys, it is a major transportation corridor.

The rapid population growth exacerbates traffic congestion and, therefore, residential, commercial, and industrial development in the Inland Empire.

In particular, it has become increasingly clogged of late with shipping container-laden trucks traveling from the ports of Los Angeles and Long Beach to rail yards and warehouses in the Inland Empire.

In the mid-2000s, the northwestern section concurrently signed with Interstate 215 underwent significant construction to improve traffic flow, but it still suffers from heavy congestion.

In 1964, California implemented a plan to simplify its highway-numbering system, where one state highway had only one route number, and concurrencies were strongly discouraged.

This left the officially designated Route 60 from Beaumont to Los Angeles orphaned from its original U.S. Highway (which to this day begins at a point on I-10 several miles east of Quartzsite, Arizona).

The signage remained as late as 1979 and had appeared in early scenes of the 1980 movie American Gigolo where Julian Kay (played by Richard Gere) is en route to Palm Springs on a "substitute" assignment.

[7] The stretch of SR 60 along the Moreno Valley Freeway made national headlines in April 2004, when five-year-old Ruby Bustamante of Indio and her 26-year-old mother, Norma, were reported missing.

Though Mrs. Bustamante died, presumably at the moment of impact, Ruby survived on her own for ten days on cups of uncooked Top Ramen noodles and bottles of Gatorade which were in the car.

On December 14, 2011, a tanker truck carrying 8,800 US gallons (33,000 L) of gasoline caught fire and exploded on the Pomona Freeway in Montebello; this caused Caltrans to rebuild the Paramount Boulevard overpass.

In mid-2016, Caltrans started constructing a partial interchange at Lemon Avenue (to Brea Canyon Road) with no westbound exit.

In addition, as part of this project, Caltrans replaced the freeway signs with retro-reflective ones from the East LA interchange to Fairway Drive.

[16] Signs between Fairway Drive and the San Bernardino-Los Angeles county line will be replaced once the widening work on SR 57 is complete.

To increase safety through the Badlands corridor between Moreno Valley and Beaumont, the Riverside County Transportation Commission (RCTC) partnered with Caltrans to complete a $138 million project to add a truck climbing lane in both directions at Gilman Springs Road and Jack Rabbit Trail.

[20] A groundbreaking ceremony was held for the future Potrero Boulevard interchange near the Jack Rabbit Trail exit of SR 60 on February 1, 2018.

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage.