High atop Montmartre is this distinctive white church, Sacré-Cœur, or "sacred heart." Constructed of travertine stone (the same used in the Arc de Triomphe), the Roman Catholic Church took nearly 40 years to complete and five more years to be consecrated (in 1919). If you choose to approach the church from below, it's around 100 steps, and if you want to climb up into the dome, it's another 270. Your reward for all that exercise is a stunning view of Paris unfolding below. Also worth noting: the basilica's campanile houses La Savoyarde, the largest bell in France, weighing in at 19 tons.