Portal:National Register of Historic Places/Portal article/13
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The City of Rocks , also known as the Silent City of Rocks, is a U.S. National Reserve and Idaho state park lying two miles (3 km) north of the south central border with Utah.
The rock spires in the City of Rocks and adjacent Castle Rocks State Park are largely composed of granitic rock of the Oligocene Almo pluton and Archean Green Creek Complex.
The California Trail passed through what is now the City of Rocks. Wagons trains of the 1840s and 1850s left the Raft River valley and traveled through the area and over Granite Pass into Nevada. The names or initials of emigrants written in axle grease are still visible on Register Rock. Ruts from wagon wheels also can be seen in some of the rocks. Learn more...