Ansel Adams

This summer, stop by the 23 U.S. locales that have risen to become UNESCO World Heritage sites

This summer, stop by the 23 U.S. locales that have risen to become UNESCO World Heritage sites

Most likely, you have been to a UNESCO World Heritage site in the United States without knowing it. Remember that Griswoldian summer vacation to the Grand Canyon? The high school field trip to Independence Hall in Philadelphia? The college tour of the University of Virginia? Congratulations! That's three in your pocket. But don't stop now. You can collect all 23, intentionally or accidentally.

For more than 40 years, the United Nations Educational, Scientific and Cultural Organization and its nearly 200 member states have been preserving, protecting and promoting the most valuable heritage places in the world. At last count, the organization has crowned 1,073 sites in more than...

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