What are National Historic Landmarks (NHL)?

National Historic Landmarks are nationally significant historic places designated by the Secretary of the Interior because they possess exceptional value or quality in illustrating or interpreting the heritage of the United States. Today, fewer than 2,500 historic places bear this national distinction. (Source: National Historic Landmarks Program Home Page)

What are Buffalo's National Historic Landmarks?

There are nine:

Guaranty Building

U.S.S. The Sullivans

Darwin Martin House

Masten Avenue (65th Regiment) Armory

Buffalo Psychiatric Center

Buffalo and Erie County Historical Society

St. Paul's Cathedral

Kleinhans Music Hall

Edward M. Cotter (former fireboat)

Where can the official list be found?

On the National Historic Landmarks Program: Lists of National Historic Landmarks (By state. Includes date of listing))

See also: City of Buffalo website (List and addresses)