Complex sentence: The day after the Butter tart festival is the Butter Tart Trot, a 5-km fun run for older people and a 2.5-km run for children under 5 years old.
Split into simpler sentences: The day after the Butter tart festival is the Butter Tart Trot. A 5 km fun run for older people and a 2.5 km run for children under 5 years old.