Peirce Mill is a historic mill located in Rock Creek Park in Northwest Washington DC. The mill was built by Isaac Peirce during the 1820s, and it ground its last commercial load of wheat in 1897, when the main shaft broke. The building served as a public teahouse until the 1930s, and, after the govenrment bought the mill in 1892, it was restored as a Public Works Administration project in 1936 and provided flour for government cafeterias from 1936 to 1958. The mill was shut down in 1993, and it was restored from 1997 to 2011 and used thereafter as a historic site.