The greenish hill west of Kathmandu stands the great stupa of Swayambhunath, a site over 2,500 years old marking the point where the legendary patriarch Manjushri discovered the lotus of the ancient Valley Lake. For centuries an important center of Buddhist learning, the painted eyes of the Buddha gaze out from all four sides of the monument. Constructed to specific rules each with a symbolic meaning, the stupa of Swayambhunath is a model of its kind. Their dazzling white hemispherical mounds represent the ladder to nirvana, itself symbolized by the umbrella on the top. The whole is hung with multi-colored prayer flags.