The immigration sign was a U.S. highway safety sign warning motorists to avoid immigrants darting across the road. It depicted a man, woman, and girl with pigtails running.

The signs were erected in response to over one hundred immigrant pedestrian deaths due to traffic collisions from 1987 to 1990 in two corridors along Interstate 5 along the San Ysidro Port of Entry at the Mexico–United States border and approximately 50 miles (80 km) north at the San Clemente United States Border Patrol checkpoint in Camp Pendleton.

The running family silhouette signs were erected starting in September 1990, and it is not known how effective they were in reducing traffic strike fatalities before the implementation of other physical measures.

A total of 10 were installed. Eventually, Caltrans built a tall fence in the I-5 median south of the San Clemente checkpoint, which effectively precluded the checkpoint-avoidance traffic-crossing tactic at Camp Pendleton, and the Border Patrol erected a tall fence along the San Diego–Tijuana border, moving illegal immigration attempts further east into the desert.

As of 2008, one sign remained in California, and there are no plans to replace it as it is largely obsolete. By February 2018, the last sign had disappeared. It was located alongside Interstate 5 near San Ysidro.

More Info: en.wikipedia.org