Tracy continued to grow as a railroad center. A new line through Los Banos was the fastest and least expensive to Los Angeles. In March of 1894 railroad headquarters at Lathrop were moved to Tracy. All of the railroad equipment including engines and buildings were moved. Thus, Tracy's beginning is in fact the story of a railroad.

Tracy was incorporated in 1910 and it grew rapidly after the first irrigation district was established in 1915. Although railroad operations began to decline in the 1950s, Tracy continued to prosper as an agricultural area. Today, the City seal reflects this history of railroads and agriculture.