In the last three years, the museum has added well over $100 million worth of art and objects, officials there estimate.
The museum is still adding galleries, education space and a restaurant.
In addition to its permanent collection, the museum adds special exhibits each year.
The museum added it to its collection, and placed the cross on display alongside other items from the war.
Now the museum (or at least the annex) adds nearly one collection a day.
His museum added America's first aquarium and expanded the wax figure department.
One way the museum adds to the collection is by belonging to a number of print clubs.
This week, the museum will add another medium to its 100,000 hours of radio and television archives.
In the following century the museum continuously added new objects to the collection.
The museum has also added a new bookshop and lecture hall.