Eiffel Tower, Paris

Initially designed as a temporary exhibit for the 1889 Exposition Universelle (World's Fair), the elegant, webbed-metal, art-nouveau design of Paris' Eiffel Tower has become the defining fixture of the French capital's skyline. Its 1st floor incorporates two glitzy glass pavilions housing interactive history exhibits; outside them, peer down through glass flooring to the ground below. Visit at dusk for the best day and night views of the glittering City of Light, and toast making it to the top at the sparkling Champagne Bar.