An Individual Time Trial (ITT) is a road bicycle race in which cyclists race alone against the clock (in French: contre la montre - literally "against the watch"). There are also track-based time trials where riders compete in velodromes, and team time trials (TTT). ITT's are also referred to as "the race of truth", as winning depends only on each rider's strength, endurance and determination against the clock. Starting times are at equal intervals, usually 30 seconds to one minute apart.

The Southern California Time Trial Series was created in 2003 to promote the sport of cycling time trial racing in Southern California, and has quickly become the most popular web site in the United States for time trial related reviews, news, and training resources.

Southern California is very competitive for time trial racing. We have over 30 individual time trial events per year, and several state championship events, as well as team time trial and pursuit track racing. For reference, standard times for men in a 20k (twenty kilometer) individual time trial (at a location such as Fiesta Island), using USCF legal aero equipment, sorted by USCF category, are:

CAT 1 = 26 mins at 28.6 MPH average 

CAT 2 = 27 mins at 27.6 MPH average

CAT 3 = 29 mins at 25.7 MPH average

CAT 4 = 31 mins at 24.0 MPH average

CAT 5 = 33 mins at 22.5 MPH average

(ref: Arnie Baker Cycling)