The Catskill Mountains became famous for Jewish resorts in the early to mid-20th Century. But such enclaves formed out of necessity — with antisemitism widespread and millions of Ku Klux Klan members nationwide.

It all started with a book: the Jewish Vacation Guide, which cataloged where Jews would be safe, well-fed and entertained. It also inspired the Green Book, a widely used guide for Black travelers.

Host Celeste Headlee speaks with Eddy Portnoy of the YIVO Institute for Jewish Research.

This article was originally published on WBUR.org.

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