DEVILS POSTPILE, a national monument (reservation) in the south-east corner of Madera county, California, U.S.A., and only a few miles south-east of Yosemite National park. The reservation (800 ac. in area) was created on July 6, 1911 to pre serve an unusual mass of hexagonal basaltic columns, like an immense pile of posts. It is said to rank with the famous Giant's Causeway in Ireland.