Which site became the first U.S. national monument under the Antiquities Act?

Devils Tower became the first U.S. national monument under the Antiquities Act.

President Theodore Roosevelt proclaimed Devils Tower National Monument on September 24, 1906, shortly after Congress passed the Antiquities Act. The Wyoming landmark is a striking volcanic formation that rises prominently above the surrounding landscape.

The Antiquities Act gave presidents authority to protect objects of historic or scientific interest on federal land by proclamation. It created a faster preservation tool than waiting for Congress to establish each protected area through separate legislation.

Devils Tower remains a National Park Service site and is sacred to many Indigenous peoples. The name “Devils Tower” is the official English designation, although the federal government has considered proposals concerning its wording and cultural context.