California 260 is an unconstructed freeway alignment that would provide access from California 61, Interstate 880, and Interstate 980 to the often-proposed but never constructed Southern Crossing (a bridge planned to cross San Francisco Bay to relieve traffic on Interstate 80/San Francisco-Oakland Bay Bridge to the north and California 92/San Mateo Bridge to the south). Although the Southern Crossing itself is not in the state highway system as a proposed state highway, the approaches (on the west via California 230 and on the west via California 260) are. At this time, there are no active plans to build California 260 absent plans to construct the bridge across the bay, excepting the section between California 61 and Interstate 880. This section, which is signed as California 61, connects Alameda with Oakland via the Webster and Posey Tubes.
Maps showing the proposed Southern Crossing as conceived in the 1960s are forthcoming.
