Final answer:
The Eiffel Tower, designed for the 1889 Exposition Universelle in Paris, and the Palace of Fine Arts, built for the 1915 Panama-Pacific International Exposition in San Francisco, are two enduring structures from World's Fairs.
Step-by-step explanation:
Two notable structures that were built for World Fairs and still exist today are the Eiffel Tower and the Palace of Fine Arts. The Eiffel Tower was constructed for the 1889 Exposition Universelle in Paris to commemorate the centennial of the French Revolution and has become an iconic symbol of France. Meanwhile, the Palace of Fine Arts was designed by Bernard Maybeck for the 1915 Panama-Pacific International Exposition in San Francisco, intended to exhibit works of art. Remarkably, both these structures were initially not intended to be permanent but have been preserved and remain popular tourist destinations.