National Historic Landmark district

generate a one-sentence description for a given conceptual class.
# Response Format
Return only the sentence: "Description: [one-sentence description of the conceptional class]"

Class: National Historic Landmark district

A National Historic Landmark district is a geographically defined area recognized by the U.S. federal government for containing a concentration of buildings, structures, sites, or landscapes that collectively possess exceptional value in illustrating or interpreting the heritage of the United States.