sandstone for the walls of campus buildings was provided by a single quarry in kom ombo, 50 kilometers north of aswan. the stone arrived by truck in giant multi-ton blocks, which were cut and shaped for walls, arches and other uses at a stone-cutting plant built on the site. the walls were constructed according to energy management systems which reduce campus air conditioning and heating energy use by at least 50 percent as compared to conventional construction methods. more than 75 percent of the stone in the alumni wall that circles the campus was recycled from stone that would otherwise have been discarded as waste after cutting.