Between the years 1891 and 1913, a total of 60 structures were erected at Fort Yellowstone, of which 35 were still in existence one hundred years later. The fort was built in two major construction waves. During the first construction period from 1891 to 1897, mainly wood-framed buildings in what has been referred to as "cottage style" were built. A few of them had Colonial Revival architectural elements. A second construction wave began in 1908 and concluded in 1913. These structures were primarily built from locally quarried sandstone. Many of the structures from the later construction period are now used as administrative offices, residences for National Park Service employees, museums and visitor center. Beyond the immediate confines of the fort, cabins were constructed for use by small detachments of army personnel while on patrol throughout the park.