Landmarks by State (Search by state, use information shown and each site has an "Official Website" link toward the bottom.)
How Stuff Works: National Historic Sites
Wikipedia - List of US Landmarks by State
Wikipedia is not generally accepted in education as a citable source; HOWEVER, it's a good place to start and then move on to the links at the bottom of the page - one of which usually is labeled "Official Site" for the landmark.
Here are websites to some of the landmarks that our library does NOT have many print resources:
Hearst San Simeon Estate/Castle, California
The Metropolitan Museum of Art
The Balsams Hotel, New Hampshire
Grand Central Station, New York City
Rockefeller Center, New York City
The Greenbrier Resort, West Virginia
The Space Needle, Seattle, Washington
Mount Washington Hotel, New Hampshire
or this one: Historic Hotels: Mt. Washington
A good way to search is in the Google SEARCH box (not address box) type your landmark name and "official site."
Online Card Catalog - Books & Materials in the Library
"American Landmarks" Book List
Username: merri
Password: mack
Use your landmark as the search term.
Includes citations!
Username: merri
Password: mack
Citations are provided!
(The Hollywood Sign, Plimouth Plantation, Empire State Building, Rockefeller Center, Metropolitan Museum of Art, Mount Rushmore, Brooklyn Bridge, Gettysburg National Military Park & Cemetery, Arlington National Cemetery, The Alamo, Monticello , Smithsonian, Hoover Dam, Washington Monument, Gateway Arch, Golden Gate Bridge, Space Needle, Mount Vernon, Liberty Bell, Statue of Liberty, Ellis Island, Santa Barbara Mission, The Hermitage)