The architectural importance of Versailles lies not in a single building but in how a building organises an entire terrain. For King Louis XIV the architect Louis Le Vau (and later Hardouin-Mansart) designed the palace, and the landscape architect André Le Nôtre the gardens; but the real work is the single geometric system the two form together.

The backbone of the composition is one great perspective axis running from the palace to the horizon. Along this axis, immediately in front of the palace, lie geometrically patterned parterres (low ornamented garden beds), then the Grand Canal and an ever-widening corridor of view framed by rows of trees. Nature here is not free; with clipped trees, aligned paths, and symmetrical pools it is turned into an architectural element, a sustained geometry. Le Nôtre, accounting for the perspective at eye level, tunes distances and proportions so that, seen from afar, the whole reads as one continuous composition.

Water is both the ornament and the engineering problem of this order: hundreds of fountains required the water gathered on the sloping site to be managed by a complex feeding and storage system. Versailles thus carries architecture out of the scale of the building into the controlled ordering of earth, plant, and water — into landscape and city planning; it becomes the founding reference for the axial city designs of the next two centuries.