Interstate 10 (I-10) is the major Interstate Highway in the southern United States. It is the southernmost transcontinental Interstate Highway in the American Interstate Highway System. It stretches from the Pacific Ocean at Interstate 1 (I-1) and State Route 1 (CA 1) in Santa Monica, California, to Interstate 95 (I-95) in Jacksonville, Florida. Major cities connected by I-10 include (from west to east) in California (Los Angeles, San Bernardino), Arizona (Phoenix, Tucson), New Mexico (Las Cruces), Texas (El Paso, San Antonio, Houston), Louisiana (Baton Rouge, New Orleans), Mississippi (Biloxi), Alabama (Mobile), and Florida (Pensacola, Tallahassee, and Jacksonville). This freeway is part of the originally planned Interstate Highway network that was laid out in 1956, and its last section was completed in 1990. I-10 is the fifth-longest Interstate Highway in the United States, following I-90, I-80, I-50, and I-40 and is one of those cross-country east-west interstate highways. About one-third of its length is within the state of Texas, where the freeway spans the state at its widest breadth, with the highest mile marker of 880. I-10 is a highway known as the Christopher Columbus Transcontinental Highway.
Between its west terminus in Santa Monica, California, and the major East Los Angeles Interchange, I-10 is known as the Santa Monica Freeway. The Santa Monica Freeway is also called the Rosa Parks Freeway for the segment beginning at I-405 (the San Diego Freeway), and ending at I-110/CA 110 (the Harbor Freeway). The segment between the East Los Angeles Interchange and the city of San Bernardino, 63 miles (101 km) long, is called the San Bernardino Freeway. Other names exist for I-10. For example, a sign near the western terminus of the highway in Santa Monica proclaims this highway the Christopher Columbus Transcontinental Highway.
I-10 is known to a considerably lesser degree as the Veterans Memorial Highway, and it is listed as a Blue Star Memorial Highway. In Palm Springs, I-10 is also named the Sonny Bono Memorial Freeway as a tribute to the late entertainer who served both as the mayor and as a U.S. Congressman. Another stretch a short distance east in Indio is proclaimed the Doctor June McCarroll Memorial Freeway.
Most of I-10 in Florida travels through some of the least-populated areas in the state, first traveling through the Florida Panhandle, where the first populated city is Pensacola, about 12 miles (20 km) from the Alabama state line, where it meets I-110, which heads south to downtown Pensacola. After the bridge over the Ochlockonee River, I-10 travels through Tallahassee, the capital of Florida, where I-10 has interchanges with FL 263, US 27, US 319, and US 90. Near Lake City, Florida, I-10 has a major interchange with I-75. Then it enters into Duval County, the last county of all of I-10's transcontinental journey, where it travels through Jacksonville, Florida's largest city. In there, I-10 expands into six lanes. Much of I-10 west of I-295 West Beltway in Jacksonville has only four lanes while east of I-295 West Beltway has six lanes and six exits and ends at I-95 west of downtown Jacksonville.
In Jacksonville, as in Arizona, I-10 is designated as the Pearl Harbor Memorial Highway. Throughout much of Florida, I-10 is also State Road 8 (FL 8), though it is not signed as such. I-110 in Pensacola is known as FL 8A.
