Paris, France, is an unusually coherent architectural creature. Paris' modern buildings have developed gradually out of earlier styles; palaces and mansions have survived by transforming into apartments and shops, and most streets harbor a range of buildings from various centuries.

Our Paris guide traces a millennium of building in Paris, and what’s amazing is that so much remains visible and integrally important to the way that Paris works, from the earliest Medieval period through the most contemporary constructions.

Paris evolved out of a walled city, and some historians argue that this alone has given Paris a certain logic that London or Boston lacks. Paris has really never lost its walls: 900 years after the 12th-century wall of Philippe August, we now live in a city walled by its ring-road, the Péripherique highway. This succession of walls, gradually torn down and rebuilt through the centuries, has created a spiraling city, which grew gradually out from the Ile de la Cité. It’s not surprising that some of the oldest buildings are near the center of the spiral.

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