"Empain envisioned a clean, spacious oasis city that would attract the indigenous and foreign elites alike... Empains city is believed to have been built on the same site as ancient Heliopolis, or On, as it was known in the Bible. That city was the womb of the Greek intellectual renaissance and a nest for great philosophers, including Plato.
Empains Heliopolis was the living image of the contemporary European ideal of a garden city. Everything was designed to forge a sense of space from the wide avenues and boulevards to public parks and squares. Noteworthy was the uniform oriental flavor of architecture, all forging the feel of a city of its own, governed by strong geometry. The Baron and his staff set strict building regulations, prohibiting any building from exceeding a height of five stories, limiting villas to a maximum height of 15 meters, and specifying that the maximum built area of any plot of land shouldnt exceed 50 percent."
Thanks to Chris Steins