South Bay Freeway / Jamacha Road
Runs from I-5 in National City to I-8 in El Cajon
Originally built as a four-lane expressway from I-805 to near Jamacha Road, it was slowly upgraded to a full freeway by the late 1990’s. Between State 125 and State 94, it remains unsigned and unbuilt. Right of way for the proposed freeway is visible in many locations along Jamacha Blvd. Highway 54 is signed again from Jamacha Junction (at State 94) to the El Cajon City Limits.
Through El Cajon, the roadway is erroneously signed as “Interstate Business Loop 54”, which was formerly State Route 54 until it was relinquished by Caltrans in the mid 1990’s.