Clear, accessible definitions for common urban planning terms.

What Is Historic Preservation?

6 minute read

Historic preservation is a controversial, highly contested cause, with a long history of failures and successes in the United States.

An image of historic Penn Station when it was first built in 1910, viewed from the outside with people, carriages, and streetcars passing by.

The historic Penn Station around the time of its completion in 1910. Penn Station was demolished to make room for Madison Square Garden. The resulting controversy is credited with creating the contemporary historic preservation movement. | Everett Collection / Shutterstock

Historic preservation is any activity that identifies, protects, rehabilitates, or enhances historic resources. In the United States, historic preservation programs at the national, state, and local levels work to identify, evaluate, designate, and maintain historic structures, objects, sites, properties, and districts. 

Historic preservation therefore operates across a spectrum of activities and typologies, and can be defined in a number of ways depending on a large number of variables.

At the federal level, the National Park Service (NPS) created the standards used to evaluate the historic significance of resources, as currently documented in the Multiple Property Documentation process.

Resources identified by the NPS can be nominated to the National Register of Historic Places, the list of historic resources designated for protection, using the evaluation criteria established by the NPS. More than 95,000 entries, encompassing over 1.8 million resources, are listed in the National Register as of this writing.

The National Historic Preservation Act of 1966 codified many of the practices of historic preservation in the United States, establishing funding methods, encouraging local historic preservation, and establishing definitions for historic preservation relative to the legal boundaries of property ownership. 

Additionally, the Antiquities Act of 1906 gave the president of the United States the authority to designate "historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest" located on federal lands. 

A privately funded, nonprofit organization called the National Trust for Historic Preservation (National Trust) works nationally to support local historic preservation efforts by managing historic sites, informing the public of historic resources and preservation efforts, and lobbying on behalf of historic preservation. 

The National Historic Preservation Act also established a State Historic Preservation Office (SHPO) with historic preservation power in each state. SHPOs will work with the National Park Service to identify and protect historic resources, and can also adopt their own programs for evaluating and designating historic resources.

Local jurisdictions also have the power to evaluate and designate historic resources. Some cities, like Los Angeles for example, have multiple historic designations—one for Historic Cultural Monuments and another for historic districts. 

At the local level, historic preservation can be wielded as a regulatory tool to influence the regulation of development and land use in neighborhoods and cities. Local preservation tools include zoning codes that establish overlays and historic districts with regulations about the size, shape, and design of new buildings and the alteration of existing buildings. Design guidelines can also implement historic preservation as policy—although design guidelines lack the same legal power as zoning codes


Some of the challenges in understanding and assessing historic preservation are caused by the debate about the definition of historic preservation. Two theorists, Eugene Viollet-le-Duc and John Ruskin, are credited with the leading concepts for preservation—despite substantial differences in their opinions on the definition of historic preservation.

Eugene Viollet-le-Duc proposes the "scrape" theory of historic preservation, which states that historic resources can be rebuilt not exactly as they were, but instead as they should have been or as they need to be now.

"To restore a building is not only to preserve it, to repair it, or to rebuild it, but to bring it back to a state of completion such as it may never have existed at any given moment." - Viollet-le-Duc in On Restoration.

John Ruskin argues for the "anti-scrape" approach—the idea that historic resources should remain untouched. Alterations, even in the for the purpose of renovating the building to current building standards, will cost a historic resource its significance. 

"...the original is then falsified, and in its restored state it is no longer an example of the art of the period to which it belonged." - John Ruskin in Lamp of Memory.


The historic preservation cause is continuously dealing with controversies—from both within its ranks and from without. 

One of these controversies has gained prominence in recent years and decades with the rise of social and racial justice movements that prioritize the representation of Black, Indigenous, and People of Color and women. In 2002, the National Park Service launched the "Cultural Heritage Needs Assessment" program to shrink the deficit of diversity in the historic preservation programs at the national, state, and local levels. Prior to the adoption of that national program, states like Alabama and Georgia pioneered new programs for representation in historic preservation in the 1980s. Many historic preservation organizations and programs now give new credit to the role of Black, Indigenous, and People of Color, as well as women, in creating and contributing to the events and culture that made resources significant. The traditionally white-centric focus of preservation is slowly, incrementally being transformed into a more honest and representative account. 

The effort continues into the present day. In August 2021, SFGate reported on a new program by staff at Muir Woods National Monument in California to document the history of indigenous custody of the land, the racist foundations of the park's founding, and the role of women in protecting the land. 

The politics and economics of development frequently provide the other source of controversy for the historic preservation cause. The debate over the definition of preservation is often signified by "façadism," a term frequently used to disparage the brand of historic preservation that leaves the exterior surfaces, or façade, of a building intact while gutting and transforming the interior of the building. The practice of adaptive reuse, or the repurposing of existing buildings for new uses with current demand from the market, often navigates the boundaries of façadism, preservation, and new development.

In the 21st century, new demand for residential lifestyles in urban centers, and the retail and restaurants that comes with significant population growth, has increased the frequency of these conflicts between historic preservation and development forces. Some cities, like Los Angeles, have completely remade dormant downtown historic districts, originally built for the commercial and entertainment purposes of the early 20th century, into bustling and expensive mixed-use neighborhoods. 

The redevelopment and adaptive reuse of historic downtowns is only one way that the development market and historic preservation can come into conflict, however. In some cities, for example, new development is allowed significant leeway to demolish and destroy historic buildings to build new. After a series of high-profile demolitions, the city of Dallas formed a new Historic Preservation Task Force and adopted a new demolition delay ordinance

In other cities, historic preservation is undeniably a powerful political force in the opposition of new development and redevelopment, which can lead to incredibly vocal and contentious controversies. There are occasions where reasonable doubts are raised about the significance of resources seeking historic preservation, thus blocking development, such as the example of an effort to protect a gas station rather than allow a proposed development in a popular, and expensive, neighborhood in Los Angeles.

Controversies from key losses of historic resources, one in New York City and one in Los Angeles, are credited with providing the historic preservation movement much of its current political power. In New York City, the demolition of historic Penn Station to make space for Madison Square Garden is credited with birthing the contemporary historic preservation movement. In Los Angeles, the destruction of the Ambassador Hotel, site of the assasination of Robert F. Kennedy, is credited with invigorating the historic preservation cause.