Complex sentence: The Great Santa Fe Trail Horse Race Endurance Ride, sometimes referred to as the Santa Fe Ride, is an annual 515-mile equine endurance ride conducted over a fourteen day period in close proximity to the historic Santa Fe Trail.
Split into simpler sentences: The Great Santa Fe Trail Horse Race Endurance Ride, sometimes referred to as the Santa Fe Ride, is an annual event. It is a 515 mile equine endurance ride conducted over a fourteen day period and in close proximity to the historic Santa Fe Trail.