XI. COMPLEX LANDSCAPES
Interactions between humans and the heavens, between microcosm and macrocosm, probably have initiated and maintained many pilgrimage traditions. Such appears to have been the case in the Nubian Desert of southern Egypt, when repetitive visits by nomadi c cattle herders during the summer monsoons between 10,000 and 7000 years before the present established a ceremonial complex and an incipient pilgrimage tradition at the Nabta Playa, involving cattle worship and megalithic structures aligned to the sun a nd stars (Malville et al 1998). The rising of the sun at its summer solstice point on the horizon coupled with the onset of the monsoon to make the desert habitable again for a few months. Since Nabta Playa is close to the Tropic of Cancer, the summer sol stice sun reached the zenith at noon, when vertical megaliths would cast no shadows. Multiple process of human life, the landscape, and the heavens were brought into resonant coupling at the time.
A similar resonance between humans, the terrestrial landscape, and the cycles of the heavens may have played a role in the development of the Chaco regional system, when the region may have been pushed into self-organized criticality by environmental f orces and population growth, resulting in a rapid onset of periodic movement of people into Chaco and construction of great houses and other accoutrements of pilgrimage (Malville and Malville 1995). Near the middle of the 11th century there may have been a sudden change as a regional system appeared with a correlation length of movement and ritual expanding from the sizes of village to distances of hundreds kilometers. The transformation of Harappan culture through the increase in correlation l ength similarly occurred very rapidly (Possehl 1990)
The tirthas of India provide further examples of self-amplifying interactions between people and their landscapes. Tirthas are "crossing-over" places with many levels of meaning. Some were initially places to pause in the process of fording a ri ver, such as the Ganga at Varanasi, at which place, the Ganga flows northward toward the place of birth. Repetition of simple acts and the confluence of countless mytho-historical events has led to the vast significance of pilgrimage to Kashi. In that lo cation multiple realms can be crossed and many of the features of self-organizing systems can be experienced such as self-similarity, resonance, and fractal geometries (Saraswati 1985; Singh, 1993; Malville and Singh 1995).