Cairo, Egypt, March 2005 - Egypt's capital, with a population of 17 million, has one of the lowest ratios of green space to urban population in the world - an area the size of a footprint per inhabitant, according to one estimate. The creation of the 30-hectare (74-acre) Al-Azhar park, undertaken in the historic district of Cairo by the The Aga Khan Trust for Culture, is proving to be a catalyst for urban renewal in one of the most congested cities in the world. The US$ 30 million project was designed as an agent for economic development, and has become a case study for creative solutions to a spectrum of challenges facing historic cities, including ecological rehabilitation.