Normally closed on Thursday, the landmark designed by Frank Lloyd Wright will observe the anniversary with free admission, guided architectural tours, screenings and other activities.

The Dulles main terminal is a well-known landmark designed by Eero Saarinen.

The current building - a landmark designed by Joseph Urban in 1926 - has only six stories.

A spokesman for the owner of 90 West, a 1907 Gothic landmark designed by Cass Gilbert, said the company was leaning toward saving the building.

As stewards of this historic landmark, designed by Stanford White at the turn of the past century, we have invested more than $2 million in upkeep and restoration.

The Opera was opened in 2008 and is a national landmark, designed by the Norwegian architectural firm, Snøhetta.

The cultural center will be housed in the restored Barakat building, also known as the "Yellow house", a historic landmark designed by Youssef Aftimus.

Fallingwater, a national architectural landmark designed by Frank Lloyd Wright.

The Sedgwick residence was a landmark designed by important American architect, Alexander Jackson Davis.

The museum would consolidate operations scattered on various parcels at Willow Run into the 1941 landmark, designed by Albert Kahn.