The Mt. SAC Relays are an annual track and field festival held primarily at Hilmer Lodge Stadium on the Mt. San Antonio College campus in Walnut, California. Originally an August event, they are now held in mid-April each year. The relays were started by then track coach Hilmer Lodge, the first edition on April 24-25, 1959. The meet attracts all levels and disciplines of the sport of Track and Field. They claim to have had as many as 9,000 competitors participate in a single year. Because of the stature of the meet, the stadium and most meet literature contains the phrase "Where the world's best athletes compete".
Mt. SAC Relays Wikipedia
While the relays are most famous for the elite division, where many notable athletes have used this event as an early season test of their fitness (before the championships that start in late May and June), there are races for small children from the community, Youth teams, and Masters athletes. A full day is largely devoted to High School events, attracting the top Southern California talent as well as others from out of town. International High School athletes from as far away as Australia and New Zealand have competed here, Mexico is represented regularly. There is a "Distance Carnival" which provides a rare (American) opportunity to run in a highly competitive track 10,000 metres race. The meet is a popular gathering for many elite throwers. Seven world records in throwing events alone, including four in the Discus have been set at the Mt. SAC Relays. A full multiple event competition associated with the meet (Decathlon for men and now Heptathlon for women) is held at Azusa Pacific University. Racewalking events are held earlier in the month, with occasional elite races held on the day of the elite competition. And with this meet being held at a Community College, there is a full competition for that level. While the relays started in 1959, the first women weren't allowed to participate until 1961, with one race, a 440 yard dash, out of a 113 event schedule.
Over the course of its history, numerous national records in athletics and world records have been set at the Mt. SAC Relays including the world record in the 4x200 Relay that lasted over 20 years (1994-2015).