National Historic Landmark

The NHL designation is reserved for properties that possess exceptional value in illustrating the heritage of the United States. To qualify, a property must meet at least one of several criteria: association with events of major historical significance, association with the lives of persons significant in U.S. history, embodiment of a distinguishing characteristic of an architectural type or engineering method, or the potential to yield information important to prehistory or history. The process begins with a nomination from the public or a federal agency, followed by a rigorous review by the National Park Service and the Advisory Board on Historic Preservation, culminating in a decision by the Secretary of the Interior.

The NHL program was established in 1960, building on earlier efforts such as the Historic Sites Act of 1935, which authorized the National Park Service to survey and document historic properties. The first designations were made in October 1960, including iconic sites like the Statue of Liberty and the Mesa Verde cliff dwellings. Over the decades, the program has expanded to include a diverse range of properties, from Native American archaeological sites to modern architectural masterpieces. In 1999, the program was streamlined to integrate with the National Register process, making nominations more efficient.

Designation as an NHL confers prestige but does not impose restrictions on private owners. Owners may use the property as they wish, provided they do not use federal funds or require federal permits. However, NHL status makes properties eligible for federal historic preservation tax incentives, including a 20% income tax credit for certified rehabilitation. Additionally, the National Park Service offers technical assistance and grants for preservation planning. While NHL designation does not automatically protect a property from demolition, it does require federal agencies to consider the impact of their actions on the property under Section 106 of the National Historic Preservation Act.

Beyond the well-known landmarks, the NHL list includes surprising entries such as the USS Constitution (the world's oldest commissioned warship afloat) and the Lucy the Margate Elephant, a six-story elephant-shaped building in New Jersey. Some NHLs are not buildings at all: the Bristol Flint Quarry in Connecticut is a prehistoric quarry site, and the Voyager Spacecraft (a pair of spacecraft) were designated in 2017 as the first NHLs in space. The program also recognizes sites of controversy, such as the Sand Creek Massacre Site, which was designated in 2022 to acknowledge a tragic chapter in U.S. history. Additionally, NHL status can be revoked if a property loses its integrity; for example, the Bishop's Palace in Galveston was delisted in 2020 after hurricane damage altered its character.

National Register of Historic Places

The official list of historic properties worthy of preservation, broader than NHL designation.

Section 106

A provision of the National Historic Preservation Act requiring federal agencies to consider effects on historic properties.

Historic Sites Act of 1935

Legislation that authorized the National Park Service to survey and document historic properties, precursor to the NHL program.