In 1961, the entire town was designated a National Historic Landmark, for its well-preserved collection of late 19th-century frontier architecture. Most of the town's buildings were built before 1900, with only modest subsequent development. The town's population continued to decline through the 1960s and 1970s. Interstate 90 bypassed Deadwood in 1964, diverting travelers and businesses. On May 21, 1980, a raid by county, state, and federal agents on the town's three remaining brothels—"The White Door", "Pam's Purple Door" and "Dixie's Green Door"—accomplished, as one reporter put it, "what Marshal Hickok never would have done","Reformers Stir Up an Old West Town" , by William C. Rempel, Los Angeles Times, July 20, 1980, p4 and the houses of prostitution were padlocked.
In 1961 the entire town was designated a National Historic Landmark, for its well-preserved collection of late 19th-century frontier architecture. ,Most of the town's buildings were built before 1900, with only modest subsequent development. The town's population continued to decline through the 1960s and 1970s. Interstate 90 bypassed Deadwood in 1964, diverting travelers and businesses. On May 21, 19,80, a raid by county, state, and federal agents on the town's three remaining brothels—"The White Door", "Pam's Purple Door" and "Dixie's Green Door"—accomplished as one reporter put it, "what Marshal Hickok never would have done","Reformers Stir Up an Old West Town" , by William C. Rempel Los Angeles Times, Jul,y 20, 1980, p4 and the houses of prostitution were padlocked.