FREE
The Sacré-Cœur Basilica, a Roman-Byzantine marvel atop Montmartre, Paris's highest point, offers free entry. Built over 40 years, it survived WWII bombings unscathed. Its 19-ton bell is among the world's heaviest. Known for its self-cleaning white stones, it was inspired by the Franco-Prussian War.
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The traveller's pocket guide
