The Four Sights
Buddhist tradition records that as a prince, Siddhartha was deliberately kept by his father from the suffering of the world. On an outing from the palace he encountered in turn an old man, a sick man, a corpse, and a wandering ascetic, and so came to see that old age, sickness, and death are inescapable, kindling the wish to leave home and seek liberation — known as the "Four Sights."
Awakening Beneath the Bodhi Tree
After six years of asceticism without liberation, Siddhartha instead accepted milk-rice from a cowherd girl to recover his strength, and sat beneath a tree at Bodh Gaya, vowing "I will not rise from this seat until I attain awakening." Tradition holds that through that night he was unmoved by the temptations and threats of Mara, and at dawn realized the Four Noble Truths, becoming the Buddha. The tree came to be called the "bodhi tree."
The First Turning of the Wheel at Deer Park
After his awakening the Buddha went to Deer Park and preached the "Four Noble Truths" (suffering, its origin, its cessation, and the path) and the "Middle Way" to the five companions who had practiced asceticism with him — the first teaching in Buddhist history, called the "First Turning of the Wheel of Dharma." All five awakened and became the earliest members of the monastic order.