The main focal point in early Buddhism for a monastic complex was the stupa. A stupa takes the form usually of a hemispherical mound. And what it represents is the burial mound of the Buddha within which his relics would have been deposited. Stupas could also have enclosed the relics of great Buddhist teachers and monks. Stupas also take the form of small containers or reliquaries, such as these stone or metal stupas in the collection of the Asian Art Museum. These would have contained the ashes of a deceased person. Stupas appear as a focal point of worship in a number of the Buddhist rock-cut sanctuaries at Ajanta and Ellora. One of the best examples of an early stupa can still be seen at Sanchi, in central India. Perched on a hill, the Great Stupa is surrounded by monastic ruins and several smaller stupas. It was built some 2,000 years ago. Four gateways were later added, marking the cardinal directions. Worshipers entered through these gateways and then walked around the stupa in a clockwise direction. The hemispherical mound was undecorated, while the gateways were elaborately carved with many scenes and figures. For example, on this gateway, the worshiper sees a voluptuous figure holding on to a fruit-bearing tree. Buddhism made use of these types of fertility deities because they had to appeal to popular taste. And so they absorbed many of these local fertility deities into their pantheon. And images such as this were considered highly auspicious, may have served to delineate the transition between sacred and secular space, as well as sanctify the site. A similar image in the Asian Art Museum galleries from a railing pillar, probably served in much the same way. The gateways here at Sanchi also contain narrative scenes, but the Buddha is never depicted in human form. His presence is indicated in this relief, for instance, by emblems of royalty like the umbrella above the horse or by his footprints. In scenes of worship, the image of the wheel or of the stupa appear to stand for the Buddha himself. So his presence is indicated by these symbols. As Buddhism spread throughout Asia, the shape of the stupa and its decoration evolved as an architectural form. In East Asia, for example, the base of the stupa tended to become taller and taller, and to add more levels, like a tower. These new, sometimes unusual forms of the stupa, continue to serve as relic chambers, and as symbols of the Buddha and his teachings.