Since the Great Exhibition in 1851, each world’s fair has chosen a theme based on the present and future concerns of its day.

The proposed theme for Expo 17 is Earth, Fire, Water, and Air—the ancient elements of life which formed the basis of science and mythology for hundreds of years.

Earth represents human habitation and our delicate relationship with the planet’s ecosystem. In tribute to this theme, a sustainable housing exhibition–-Habitat 2017–-and a horticultural exhibition will be held along with Expo 17.

Fire represents light and energy, as well as community and celebration. To honour this theme, Expo 17 will be a Bureau International des Expositions (BIE) recognised exposition–-an official gathering of nations.

Water is the source of life. To realise this theme, the remediation of the banks of the Saint Lawrence River will bring life back to its waters.

Air denotes freedom and well-being. In honour of this theme, Montreal’s renowned historical section, Old Montreal, will be turned into a car-free zone.