Ennis-Brown House

Los Angeles' Ennis-Brown House is among 11 sites on The National Trust for Historic Preservation's 2005 list of the most endangered historic places in America. Built in 1924, the grandest of Frank Lloyd Wright's textile-block houses was badly damaged by a 1994 earthquake and recent rains. It's unsafe for visitors, and stabilization costs would be about $5 million.

Credit: nationaltrust.org