Vallejo, California, is a vibrant city located in Solano County, just north of San Francisco. With a rich history dating back to the 19th century, Vallejo has played a significant role in the transportation industry, particularly in regards to freight. The city's strategic location on the Carquinez Strait made it an ideal hub for shipping goods by both land and sea.

One of Vallejo's most notable contributions to freight transportation is its historic Mare Island Naval Shipyard. Established in 1854, Mare Island quickly became one of the most important shipbuilding facilities on the West Coast. During its peak, the shipyard employed over 46,000 workers and was responsible for constructing and repairing numerous naval vessels, including battleships, cruisers, and submarines. The shipyard played a crucial role in supporting the U.S. Navy's operations during World War II and the Cold War. Although the shipyard closed in 1996, its legacy as a key player in the freight transportation industry lives on.